avnc 019

018_Conditional_branching_and_looping/018_csharp.md

@@ -1,4 +1,6 @@
-# Guided project - Develop conditional branching and looping structures in C#
+# Guided project
+
+## Develop conditional branching and looping structures in C#
 
 Gain experience developing a console app that implements selection and
 iteration statements to achieve app specifications.
@@ -183,3 +185,9 @@ can unzip the files in a sandbox or hosted environment.
 You're now ready to begin the Guided project exercises. Good luck!
 
 ---
+
+Project Files
+
+- [Starter](./GuidedProject/Starter/Program.cs)
+- [Final](./GuidedProject/Final/Program.cs)
+- [Own](./GuidedProject/Own/Program.cs)

018_Conditional_branching_and_looping/GuidedProject/Own/Program.cs

@@ -1,12 +1,25 @@
 int max_pets = 8;
 bool exit = false;
 string? selection;
-string separator = "+------------------------------------------" +
+string separator = "+-------------------------------------" +
-                   "--------------------------------------------+";
+                   "--------------------------------------+";
+string main_menu = @"
+    1. List all of our current pet information.
+    2. Assign values to the ourAnimals array fields.
+    3. Ensure animal ages and physical descriptions are complete.
+    4. Ensure animal nicknames and personality descriptions are complete.
+    5. Edit an animal's age.
+    6. Edit an animal's personality description.
+    7. Display all cats with a specified characteristic.
+    8. Display all dogs with a specified characteristic.
+
+  Enter menu item selection or type 'Exit' to exit the program
+";
 string[] description = {
     "big sized female golden colored weighing about 20 pounds. housebroken.",
     "large dark-brown male siver back weighing about 15 pounds. housebroken.",
     "small white female weighing about 8 pounds. translucid at sun.",
+    "medium size male. fluorescent at night.",
 };
 string[] personality = {
     "friendly",
@@ -14,18 +27,6 @@ string[] personality = {
     "loves to have her belly rubbed. gives lots of kisses.",
     "sauvage and lovelly.",
 };
-string main_menu = @"
-    1. List all of our current pet information.
-    2. Assign values to the ourAnimals array fields.
-    3. Ensure animal ages and physical descriptions are complete.
-    4. Ensure animal nicknames and personality descriptions are complete.
-    5. Edit an animal’s age.
-    6. Edit an animal’s personality description.
-    7. Display all cats with a specified characteristic.
-    8. Display all dogs with a specified characteristic.
-
-  Enter menu item selection or type 'Exit' to exit the program
-";
 string[] options = { "1", "2", "3", "4", "5", "6", "7", "8", "exit" };
 string[] nickname = { "lola", "loki", "fuzz", "boby", "gogo", "besti" };
 string[] species = { "cat", "dog", "bee", "pig" };
@@ -86,6 +87,7 @@ void press_enter() {
 }
 
 void print_pets(string[,] animals) {
+    clear();
     print(separator);
     for (int j = 0; j < animals.GetLength(0); j++) {
         string[] animal = new string[6];
@@ -113,6 +115,99 @@ void print_pet(string[] pet) {
     }
 }
 
+int availability(string[,] animals) {
+    int pet_count = 0;
+    for (int j = 0; j < animals.GetLength(0); j++) {
+        if (!string.IsNullOrEmpty(animals[j, 1])) {
+            pet_count++;
+        }
+    }
+    int slots = max_pets - pet_count;
+    return slots;
+}
+
+string get_input(string text="Please enter your text: ", bool integer=false) {
+    bool invalid = true;
+    while (invalid){
+        print(text, false);
+        string? usr_in = Console.ReadLine();
+        if (!string.IsNullOrEmpty(usr_in) && usr_in.Trim() != "") {
+            if (integer) {
+                string resp = usr_in.Trim();
+                int temp_int;
+                if (int.TryParse(resp, out temp_int)) {
+                    print($"Opción 1: {temp_int}");
+                    return resp;
+                }
+            } else {
+                return usr_in.Trim();
+            }
+        }
+    }
+    return "";
+}
+
+void add_new_pet(string[,] animals, int slots){
+    int at_indx = max_pets - slots;
+    string id = $"{rand_str(abcd)}{rand_int(nums)}";
+    string specie = get_input("Enter pet specie: ");
+    string name = get_input("Enter the pet name: ");
+    int age = Int32.Parse(get_input("Enter pet age: ", true));
+    string desc = get_input("Enter the physical description: ");
+    string perso = get_input("Enter pet personality: ");
+    //print($"Will be added at index: {at_indx}");
+    //print($"{id}\n{specie}\n{name}\n{age}\n{desc}\n{perso}");
+    animals[at_indx, 0] = specie;
+    animals[at_indx, 1] = id;
+    animals[at_indx, 2] = desc;
+    animals[at_indx, 3] = age.ToString();
+    animals[at_indx, 4] = perso;
+    animals[at_indx, 5] = name;
+}
+
+void ask_new_pet() {
+    clear();
+    print("Assign values to the ourAnimals array fields");
+    print(separator);
+    int slots = availability(our_animals);
+    print($"\nWe currently have {max_pets-slots} pets that need homes.");
+    print($"We can manage {slots} more.");
+    if (slots > 0) {
+        bool another = false;
+        do {
+            string resp = get_input("Do you want to enter info for another pet?: ");
+            bool invalid = true;
+            if (resp != "") {
+                while(invalid) {
+                    switch (resp) {
+                        case "y" or "yes":
+                            add_new_pet(our_animals, slots);
+                            resp = "";
+                            invalid = false;
+                            another = true;
+                            break;
+                        case "n" or "no":
+                            invalid = false;
+                            another = false;
+                            break;
+                        default:
+                            resp = get_input("Please enter [Y]es or [N]o: ");
+                            break;
+                    }
+                }
+            }
+            slots = availability(our_animals);
+        } while (another && slots > 0);
+        if (slots == 0) {
+            print("We have reached our limit on the number of pets that we can manage.");
+            press_enter();
+        }
+        press_enter();
+    } else {
+        press_enter();
+    }
+}
+
 populate_animals_array();
 while (!exit) {
     clear();
@@ -122,14 +217,11 @@ while (!exit) {
         selection = selection.ToLower();
         switch (selection) {
             case "1":
-                clear();
                 print_pets(our_animals);
                 press_enter();
                 break;
             case "2":
-                clear();
+                ask_new_pet();
-                print("Assign values to the ourAnimals array fields");
-                press_enter();
                 break;
             case "3":
                 clear();
@@ -143,12 +235,12 @@ while (!exit) {
                 break;
             case "5":
                 clear();
-                print("Edit an animal’s age");
+                print("Edit an animal's age");
                 press_enter();
                 break;
             case "6":
                 clear();
-                print("Edit an animal’s personality description");
+                print("Edit an animal's personality description");
                 press_enter();
                 break;
             case "7":
@@ -162,7 +254,7 @@ while (!exit) {
                 press_enter();
                 break;
             case "exit":
-                print("\n\tFinalizando aplicación\n");
+                print("\n\tTerminating application\n");
                 exit = !exit;
                 break;
             default:

019_branching_and_looping_structures/019_csharp.md

@@ -0,0 +1,409 @@
+# Challenge project
+
+## Develop branching and looping structures in C#
+
+Demonstrate your ability to develop a console app that implements selection and
+iteration statements to achieve app specifications.
+
+### Learning objectives
+
+In this module, you'll demonstrate your ability to:
+
+- Use Visual Studio Code to develop a C# console application that uses a
+combination of selection and iteration statements to implement logical
+workflows in accordance with supplied application data and user interactions.
+- Evaluate the underlying conditions and make an informed decision when
+choosing between if-elseif-else and switch statements, and between foreach,
+for, while, and do iteration statements.
+- Scope variables at an appropriate level within an application.
+
+## Introduction
+
+Applications often use a combination of selection and iteration statements to
+establish code execution paths. In addition, user input and calculations
+influence the flow through an application. Creating a user interface that
+implements a design specification can be challenging.
+
+Suppose you're a developer working on the Contoso Pets application, an
+application that's used to find homes for stray or abandoned pets. Some of the
+development work has already been completed. For example, the application's
+main menu and the code used to store new pet information have been developed.
+However, certain information isn't always available when a pet is entered in
+your system. You need to develop the features that ensure a complete dataset
+exists for each animal in your care.
+
+In this module, you'll develop the following features of the Contoso Pets
+application:
+
+- A feature that ensures animal ages and physical descriptions are complete.
+- A feature that ensures animal nickname and personality descriptions are
+complete.
+
+By the end of this module, your Contoso Pets application will ensure that every
+element in the ourAnimals array is complete.
+
+> Note  
+> This is a challenge project module where you’ll complete an end-to-end
+project from a specification. This module is intended to be a test of your
+skills; there’s little guidance and no step-by-step instructions.
+
+### Learning Objectives
+
+In this module, you'll demonstrate your ability to:
+
+- Develop a C# console application that uses a combination of selection and
+iteration statements to implement logical workflows.
+- Evaluate the underlying conditions in your application and make an informed
+decision between selection statement options.
+- Scope variables at an appropriate level within an application.
+
+---
+
+## Prepare
+
+In this challenge project, you'll develop portions of a C# console application.
+You'll use boolean expressions, selection statements, and iteration statements
+to implement the features of a design specification. As you develop the
+application, you'll need to scope variables at the appropriate level.
+
+### Project specification
+
+The Starter code project for this module includes a Program.cs file with the
+following code features:
+
+- The code declares variables used to collect and process pet data and menu item
+selections
+
+- The code declares the ourAnimals array that includes the following information
+for each animal in the array:
+
+  - Pet ID #.
+  - Pet species (cat or dog).
+  - Pet age (years).
+  - A description of the pet's physical appearance.
+  - A description of the pet's personality.
+  - The pet's nickname.
+
+- The code uses a for loop around a `switch-case` construct to populate elements
+of the `ourAnimals` array.
+
+- The code includes a loop around a main menu that terminates when the user
+enters "exit". The main menu includes:
+
+```txt
+1. List all of our current pet information.
+2. Assign values to the ourAnimals array fields.
+3. Ensure animal ages and physical descriptions are complete.
+4. Ensure animal nicknames and personality descriptions are complete.
+5. Edit an animal’s age.
+6. Edit an animal’s personality description.
+7. Display all cats with a specified characteristic.
+8. Display all dogs with a specified characteristic.
+
+Enter menu item selection or type "Exit" to exit the program
+```
+
+- The code reads the user's menu item selection and uses a switch statement to
+branch the code for each menu item number.
+
+- The code includes implementation for menu options 1 and 2.
+
+- The code displays an "under construction" message for menu options 3-8.
+
+Your goal in this challenge is to create the app features aligned with menu
+options 3 and 4.
+
+> Note  
+> New animals must be added to the ourAnimals array when they arrive. However,
+an animal's age and some physical characteristics for a pet may be unknown
+until after a veterinarian's examination. In addition, an animal's nickname and
+personality may be unknown when a pet first arrives. The new features that
+you're developing will ensure that a complete dataset exists for each animal in
+the ourAnimals array.
+
+To ensure that animal ages and physical descriptions are complete, your code
+must:
+
+- Assign a valid numeric value to petAge for any animal that has been assigned
+data in the ourAnimals array but has not been assigned an age.
+- Assign a valid string to petPhysicalDescription for any animal that has been
+assigned data in the ourAnimals array but has not been assigned a physical
+description.
+- Verify that physical descriptions have an assigned value. Assigned values
+cannot have zero characters. Any further requirement is up to you.
+- To ensure that animal nicknames and personality descriptions are complete,
+your code must:
+
+- Assign a valid string to petNickname for any animal that has been assigned
+data in the ourAnimals array but has not been assigned a nickname.
+- Assign a valid string to petPersonalityDescription for any animal that has
+been assigned data in the ourAnimals array but has not been assigned a
+personality description.
+- Verify that nicknames and personality descriptions have an assigned value.
+Assigned values cannot have zero characters. Any further requirement is up to
+you.
+
+### Setup
+
+Use the following steps to prepare for the Challenge project exercises:
+
+To download a zip file containing the Starter project code, select the
+following link:
+[Lab Files](https://github.com/MicrosoftLearning/Challenge-project-branching-looping-CSharp/archive/refs/heads/main.zip).
+
+Unzip the files in your development environment. Consider using your PC as your
+development environment so that you have access to your code after completing
+this module. If you aren't using your PC as your development environment, you
+can unzip the files in a sandbox or hosted environment.
+
+You're now ready to begin the Challenge project exercises. Good luck!
+
+---
+
+## Exercise
+
+### Ensure that petAge and petPhysicalDescription contain valid information
+
+The Contoso Pets application is used to help find new homes for abandoned pets.
+Your goal in this challenge is to develop the application features used to
+ensure that you have a completed dataset for each animal in the ourAnimals array.
+
+### Specification
+
+In this challenge exercise, you need to develop a feature that ensures animal
+ages and physical descriptions are complete.
+
+This feature must:
+
+- Be enabled inside the appropriate application branch (must not overwrite the
+code in the code branch for menu option 2).
+
+- Skip over any animal in the ourAnimals array when the value of pet ID is set
+to the default value.
+
+- Display the pet ID value and prompt the user for an updated data value if
+ourAnimals array data is missing or incomplete.
+
+- Ensure that a valid numeric value is assigned to animalAge for all animals in
+the ourAnimals array that have assigned data.
+
+- Ensure that a valid string is assigned to animalPhysicalDescription for all
+animals in the ourAnimals array that have assigned data.
+
+- Enforce the following validation rules for animalAge.
+
+  - It must be possible to convert the value entered to numeric data type.
+
+- Enforce the following validation rules for animalPhysicalDescription:
+
+    - Values cannot be null.
+    - Values cannot have zero characters.
+    - Any further restriction is up to the developer.
+
+- Inform the application user when all data requirements are met, pausing the
+application to ensure the message can be seen and responded to.
+
+### Check your work
+
+To validate that your code satisfies the specified requirements
+
+> Note  
+> You can exit the verification test before completing all of the verification
+steps if see a result that does not satisfy the specification requirements. To
+force an exit from the running program, in the Terminal panel, press Ctrl-C.
+After exiting the running app, complete the edits that you believe will address
+the issue you are working on, save your updates to the Program.cs file, and
+then re-build and run your code.
+
+At the Terminal command prompt, enter 3
+
+Verify that the Terminal panel updates with a message similar to the following:
+
+```txt
+Enter an age for ID #: c4
+```
+
+At the Terminal command prompt, enter one
+
+Verify that your code repeats the prompt requesting a value for the age of the
+pet.
+
+The Terminal panel should update to show the repeated prompt. The display
+should be similar to the following:
+
+```txt
+Enter an age for ID #: c4
+one
+Enter an age for ID #: c4
+```
+
+At the Terminal command prompt, enter 1
+
+Verify that your code accepts 1 as a valid numeric entry and that the Terminal
+panel displays a message similar to the following:
+
+```txt
+Enter a physical description for ID #: c4 (size, color, breed, gender, weight, housebroken)
+```
+
+At the Terminal command prompt, press the Enter key (without typing any characters).
+
+Verify that your code repeats the prompt requesting a value for the physical
+description of the pet.
+
+The Terminal panel should update to show the repeated prompt. The display
+should be similar to the following:
+
+```txt
+Enter a physical description for ID #: c4 (size, color, gender, weight, housebroken)
+
+Enter a physical description for ID #: c4 (size, color, gender, weight, housebroken)
+```
+
+At the Terminal command prompt, enter small white Siamese cat weighing about 8
+pounds. litter box trained.
+
+Verify that your code accepts small white Siamese cat weighing about 8 pounds.
+litter box trained. as a valid entry and that the Terminal panel displays a
+message similar to the following:
+
+```txt
+Age and physical description fields are complete for all of our friends.
+Press the Enter key to continue
+```
+
+If you specified further restrictions for valid entries, run the appropriate
+test cases to verify your work.
+
+> Note  
+> If your code meets the requirements you should be able to complete each step
+in order and see the expected results in a single test pass. If you added
+additional restrictions, you may need to exit the application and then run a
+separate test pass to complete your verification.
+
+Once you've validated the results for this exercise, proceed to the next
+exercise in this challenge.
+
+## Exercise
+
+### Ensure that pet nicknames and personality descriptions are complete
+
+The Contoso Pets app is used to help find new homes for abandoned pets. Your
+goal in this challenge is to develop the app features used to ensure that we
+have a completed dataset for each animal in the ourAnimals array.
+
+### Specification
+
+You need to develop a feature that ensures animal nicknames and personality
+descriptions are complete.
+
+This feature must:
+
+- Be enabled inside the appropriate application branch (must not overwrite the
+code in the code branch for menu option 2).
+
+- Skip over any animal in the ourAnimals array when the value of pet ID is set
+to the value default value.
+
+- Display the pet ID value and prompt the user for an updated data value if
+ourAnimals array data is missing or incomplete.
+
+- Ensure that a valid string is assigned to animalNickname for all animals in
+the ourAnimals array that have assigned data.
+
+- Ensure that a valid string is assigned to animalPersonalityDescription for
+all animals in the ourAnimals array that have assigned data.
+
+- Enforce the following validation rules for petNickname and
+petPersonalityDescription:
+
+  - Values cannot be null.
+  - Values cannot have zero characters.
+  - Any further restriction is up to the developer.
+
+Inform the application user when all data requirements are met, pausing the
+application to ensure the message can be seen and responded to.
+
+### Check your work
+
+To validate that your code satisfies the specified requirements, complete the
+following steps:
+
+Build and run your app.
+
+At the Terminal command prompt, enter 4
+
+Verify that the Terminal panel updates with a message similar to the following:
+
+```txt
+Enter a nickname for ID #: c4
+```
+
+At the Terminal command prompt, press the Enter key (without typing any
+characters).
+
+Verify that your code repeats the prompt requesting a value for the nickname of
+the pet.
+
+The Terminal panel should update to display something similar to the following:
+
+```txt
+Enter a nickname for ID #: c4
+
+Enter a nickname for ID #: c4
+```
+
+At the Terminal command prompt, enter snowflake
+
+Verify that your code accepts snowflake as a valid entry and that the Terminal
+panel displays a message similar to the following:
+
+```txt
+Enter a personality description for ID #: c4 (likes or dislikes, tricks, energy level)
+```
+
+At the Terminal command prompt, press the Enter key (without typing any
+characters).
+
+Verify that your code repeats the prompt requesting a value for the personality
+description of the pet.
+
+The Terminal panel should update to display something similar to the following:
+
+```txt
+Enter a personality description for ID #: c4 (likes or dislikes, tricks, energy level)
+
+Enter a personality description for ID #: c4 (likes or dislikes, tricks, energy level)
+```
+
+At the Terminal command prompt, enter loves to curl up in a warm spot
+
+Verify that your code accepts loves to curl up in a warm spot as a valid entry
+and that the Terminal panel displays a message similar to the following:
+
+```txt
+Nickname and personality description fields are complete for all of our friends. 
+Press the Enter key to continue
+```
+
+If you specified further restrictions for valid entries, run the appropriate
+test cases to verify your work.
+
+Congratulations if you succeeded in this challenge!
+
+---
+
+## Summary
+
+Your goal was to demonstrate the ability to develop features of an application
+that achieve a design specification. You needed to choose and implement the
+appropriate iteration and selection statement types to meet the stated
+requirements.
+
+By creating nested combinations of iteration and selection statements, you
+built a user interface that enables the application user to enter valid pet
+data that filled gaps in the ourAnimals array.
+
+Your ability to implement features of the Contoso Pets application based on a
+design specification demonstrates your understanding of the iteration and
+selection statements.

019_branching_and_looping_structures/ChallengeProject/Final/Final.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

019_branching_and_looping_structures/ChallengeProject/Final/Program.cs

@@ -0,0 +1,434 @@
+using System;
+using System.IO;
+
+// the ourAnimals array will store the following: 
+string animalSpecies = "";
+string animalID = "";
+string animalAge = "";
+string animalPhysicalDescription = "";
+string animalPersonalityDescription = "";
+string animalNickname = "";
+
+// variables that support data entry
+int maxPets = 8;
+string? readResult;
+string menuSelection = "";
+int petCount = 0;
+string anotherPet = "y";
+bool validEntry = false;
+int petAge = 0;
+
+// array used to store runtime data, there is no persisted data
+string[,] ourAnimals = new string[maxPets, 6];
+
+// create some initial ourAnimals array entries
+for (int i = 0; i < maxPets; i++)
+{
+    switch (i)
+    {
+        case 0:
+            animalSpecies = "dog";
+            animalID = "d1";
+            animalAge = "2";
+            animalPhysicalDescription = "medium sized cream colored female golden retriever weighing about 65 pounds. housebroken.";
+            animalPersonalityDescription = "loves to have her belly rubbed and likes to chase her tail. gives lots of kisses.";
+            animalNickname = "lola";
+            break;
+
+        case 1:
+            animalSpecies = "dog";
+            animalID = "d2";
+            animalAge = "9";
+            animalPhysicalDescription = "large reddish-brown male golden retriever weighing about 85 pounds. housebroken.";
+            animalPersonalityDescription = "loves to have his ears rubbed when he greets you at the door, or at any time! loves to lean-in and give doggy hugs.";
+            animalNickname = "loki";
+            break;
+
+        case 2:
+            animalSpecies = "cat";
+            animalID = "c3";
+            animalAge = "1";
+            animalPhysicalDescription = "small white female weighing about 8 pounds. litter box trained.";
+            animalPersonalityDescription = "friendly";
+            animalNickname = "Puss";
+            break;
+
+        case 3:
+            animalSpecies = "cat";
+            animalID = "c4";
+            animalAge = "?";
+            animalPhysicalDescription = "";
+            animalPersonalityDescription = "";
+            animalNickname = "";
+
+            break;
+
+        default:
+            animalSpecies = "";
+            animalID = "";
+            animalAge = "";
+            animalPhysicalDescription = "";
+            animalPersonalityDescription = "";
+            animalNickname = "";
+            break;
+
+    }
+
+    ourAnimals[i, 0] = "ID #: " + animalID;
+    ourAnimals[i, 1] = "Species: " + animalSpecies;
+    ourAnimals[i, 2] = "Age: " + animalAge;
+    ourAnimals[i, 3] = "Nickname: " + animalNickname;
+    ourAnimals[i, 4] = "Physical description: " + animalPhysicalDescription;
+    ourAnimals[i, 5] = "Personality: " + animalPersonalityDescription;
+}
+
+// display the top-level menu options
+do
+{
+    Console.Clear();
+
+    Console.WriteLine("Welcome to the Contoso PetFriends app. Your main menu options are:");
+    Console.WriteLine(" 1. List all of our current pet information");
+    Console.WriteLine(" 2. Add a new animal friend to the ourAnimals array");
+    Console.WriteLine(" 3. Ensure animal ages and physical descriptions are complete");
+    Console.WriteLine(" 4. Ensure animal nicknames and personality descriptions are complete");
+    Console.WriteLine(" 5. Edit an animal’s age");
+    Console.WriteLine(" 6. Edit an animal’s personality description");
+    Console.WriteLine(" 7. Display all cats with a specified characteristic");
+    Console.WriteLine(" 8. Display all dogs with a specified characteristic");
+    Console.WriteLine();
+    Console.WriteLine("Enter your selection number (or type Exit to exit the program)");
+
+    readResult = Console.ReadLine();
+    if (readResult != null)
+    {
+        menuSelection = readResult.ToLower();
+        // NOTE: We could put a do statement around the menuSelection entry to ensure a valid entry, but we
+        //  use a conditional statement below that only processes the valid entry values, so the do statement 
+        //  is not required here. 
+    }
+
+    // use switch-case to process the selected menu option
+    switch (menuSelection)
+    {
+        case "1":
+            // List all of our current pet information
+            for (int i = 0; i < maxPets; i++)
+            {
+                if (ourAnimals[i, 0] != "ID #: ")
+                {
+                    Console.WriteLine();
+                    for (int j = 0; j < 6; j++)
+                    {
+                        Console.WriteLine(ourAnimals[i, j].ToString());
+                    }
+                }
+            }
+            Console.WriteLine("\n\rPress the Enter key to continue");
+            readResult = Console.ReadLine();
+
+            break;
+
+        case "2":
+            // Add a new animal friend to the ourAnimals array
+            //
+            // The ourAnimals array contains
+            //    1. the species (cat or dog). a required field
+            //    2. the ID number - for example C17
+            //    3. the pet's age. can be blank at initial entry.
+            //    4. the pet's nickname. can be blank.
+            //    5. a description of the pet's physical appearance. can be blank.
+            //    6. a description of the pet's personality. can be blank.
+
+            anotherPet = "y";
+            petCount = 0;
+            for (int i = 0; i < maxPets; i++)
+            {
+                if (ourAnimals[i, 0] != "ID #: ")
+                {
+                    petCount += 1;
+                }
+            }
+
+            if (petCount < maxPets)
+            {
+                Console.WriteLine($"We currently have {petCount} pets that need homes. We can manage {(maxPets - petCount)} more.");
+            }
+
+            while (anotherPet == "y" && petCount < maxPets)
+            {
+                // get species (cat or dog) - string animalSpecies is a required field 
+                do
+                {
+                    Console.WriteLine("\n\rEnter 'dog' or 'cat' to begin a new entry");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalSpecies = readResult.ToLower();
+                        if (animalSpecies != "dog" && animalSpecies != "cat")
+                        {
+                            //Console.WriteLine($"You entered: {animalSpecies}.");
+                            validEntry = false;
+                        }
+                        else
+                        {
+                            validEntry = true;
+                        }
+                    }
+                } while (validEntry == false);
+
+                // build the animal the ID number - for example C1, C2, D3 (for Cat 1, Cat 2, Dog 3)
+                animalID = animalSpecies.Substring(0, 1) + (petCount + 1).ToString();
+
+                // get the pet's age. can be ? at initial entry.
+                do
+                {
+                    Console.WriteLine("Enter the pet's age or enter ? if unknown");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalAge = readResult;
+                        if (animalAge != "?")
+                        {
+                            validEntry = int.TryParse(animalAge, out petAge);
+                        }
+                        else
+                        {
+                            validEntry = true;
+                        }                        
+                    }
+                } while (validEntry == false);
+
+
+                // get a description of the pet's physical appearance - animalPhysicalDescription can be blank.
+                do
+                {
+                    Console.WriteLine("Enter a physical description of the pet (size, color, gender, weight, housebroken)");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalPhysicalDescription = readResult.ToLower();
+                        if (animalPhysicalDescription == "")
+                        {
+                            animalPhysicalDescription = "tbd";
+                        }
+                    }
+                } while (validEntry == false);
+
+
+                // get a description of the pet's personality - animalPersonalityDescription can be blank.
+                do
+                {
+                    Console.WriteLine("Enter a description of the pet's personality (likes or dislikes, tricks, energy level)");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalPersonalityDescription = readResult.ToLower();
+                        if (animalPersonalityDescription == "")
+                        {
+                            animalPersonalityDescription = "tbd";
+                        }
+                    }
+                } while (validEntry == false);
+
+
+                // get the pet's nickname. animalNickname can be blank.
+                do
+                {
+                    Console.WriteLine("Enter a nickname for the pet");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalNickname = readResult.ToLower();
+                        if (animalNickname == "")
+                        {
+                            animalNickname = "tbd";
+                        }
+                    }
+                } while (validEntry == false);
+
+                // store the pet information in the ourAnimals array (zero based)
+                ourAnimals[petCount, 0] = "ID #: " + animalID;
+                ourAnimals[petCount, 1] = "Species: " + animalSpecies;
+                ourAnimals[petCount, 2] = "Age: " + animalAge;
+                ourAnimals[petCount, 3] = "Nickname: " + animalNickname;
+                ourAnimals[petCount, 4] = "Physical description: " + animalPhysicalDescription;
+                ourAnimals[petCount, 5] = "Personality: " + animalPersonalityDescription;
+
+                // increment petCount (the array is zero-based, so we increment the counter after adding to the array)
+                petCount = petCount + 1;
+
+                // check maxPet limit
+                if (petCount < maxPets)
+                {
+                    // another pet?
+                    Console.WriteLine("Do you want to enter info for another pet (y/n)");
+                    do
+                    {
+                        readResult = Console.ReadLine();
+                        if (readResult != null)
+                        {
+                            anotherPet = readResult.ToLower();
+                        }
+
+                    } while (anotherPet != "y" && anotherPet != "n");
+                }
+                //NOTE: The value of anotherPet (either "y" or "n") is evaluated in the while statement expression - at the top of the while loop
+            }
+
+            if (petCount >= maxPets)
+            {
+                Console.WriteLine("We have reached our limit on the number of pets that we can manage.");
+                Console.WriteLine("Press the Enter key to continue.");
+                readResult = Console.ReadLine();
+            }
+
+            break;
+
+        case "3":
+            // Ensure animal ages and physical descriptions are complete
+            //
+            //    ourAnimals[i, 2] = "Age: " + animalAge;
+            //    ourAnimals[i, 4] = "Physical description: " + animalPhysicalDescription;
+
+            for (int i = 0; i < maxPets; i++)
+            {
+                if (ourAnimals[i, 2] == "Age: ?" && ourAnimals[i, 0] != "ID #: ")
+                {
+                    do
+                    {
+                        Console.WriteLine($"Enter an age for {ourAnimals[i, 0]}");
+                        readResult = Console.ReadLine();
+                        if (readResult != null)
+                        {
+                            animalAge = readResult;
+                            validEntry = int.TryParse(animalAge, out petAge);
+                        }
+                    } while (validEntry == false);
+                    ourAnimals[i, 2] = "Age: " + animalAge.ToString();
+                }
+
+                if (ourAnimals[i, 4] == "Physical description: " && ourAnimals[i, 0] != "ID #: ")
+                {
+                    do
+                    {
+                        Console.WriteLine($"Enter a physical description for {ourAnimals[i, 0]} (size, color, gender, weight, housebroken)");
+                        readResult = Console.ReadLine();
+                        if (readResult != null)
+                        {
+                            animalPhysicalDescription = readResult.ToLower();
+                            if (animalPhysicalDescription == "")
+                            {
+                                validEntry = false;
+                            }
+                            else
+                            {
+                                validEntry = true;
+                            }
+
+                        }
+                    } while (validEntry == false);
+
+                    ourAnimals[i, 4] = "Physical description: " + animalPhysicalDescription;
+                }
+            }
+            Console.WriteLine("\n\rAge and physical description fields are complete for all of our friends. \n\rPress the Enter key to continue");
+            readResult = Console.ReadLine();
+
+            break;
+
+        case "4":
+            // Ensure animal nickname and personality descriptions are complete
+            //
+            //    ourAnimals[i, 3] = "Nickname: " + animalNickname;
+            //    ourAnimals[i, 5] = "Personality: " + animalPersonalityDescription;
+
+            for (int i = 0; i < maxPets; i++)
+            {
+                if (ourAnimals[i, 3] == "Nickname: " && ourAnimals[i, 0] != "ID #: ")
+                {
+                    do
+                    {
+                        Console.WriteLine($"Enter a nickname for {ourAnimals[i, 0]}");
+                        readResult = Console.ReadLine();
+                        if (readResult != null)
+                        {
+                            animalNickname = readResult;
+                            if (animalNickname == "")
+                            {
+                                validEntry = false;
+                            }
+                            else
+                            {
+                                validEntry = true;
+                            }
+
+                        }
+
+                    } while (validEntry == false);
+
+                    ourAnimals[i, 3] = "Nickname: " + animalNickname;
+                }
+
+                if (ourAnimals[i, 5] == "Personality: " && ourAnimals[i, 0] != "ID #: ")
+                {
+                    do
+                    {
+                        //"Enter a description of the pet's personality (likes or dislikes, tricks, energy level"
+                        Console.WriteLine($"Enter a personality description for {ourAnimals[i, 0]} (likes or dislikes, tricks, energy level)");
+                        readResult = Console.ReadLine();
+                        if (readResult != null)
+                        {
+                            animalPersonalityDescription = readResult.ToLower();
+                            if (animalPersonalityDescription == "")
+                            {
+                                validEntry = false;
+                            }
+                            else
+                            {
+                                validEntry = true;
+                            }
+                        }
+                    } while (validEntry == false);
+
+                    ourAnimals[i, 5] = "Personality: " + animalPersonalityDescription;
+                }
+            }
+            Console.WriteLine("\n\rAge and physical description fields are complete for all of our friends. \n\rPress the Enter key to continue");
+            readResult = Console.ReadLine();
+
+            break;
+
+        case "5":
+            // Edit an animal’s age");
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        case "6":
+            // Edit an animal’s personality description");
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+        
+        case "7":
+            // Display all cats with a specified characteristic
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        case "8":
+            // Display all dogs with a specified characteristic
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        default:
+            break;
+    }
+
+} while (menuSelection != "exit");

019_branching_and_looping_structures/ChallengeProject/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Microsoft Learning
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

019_branching_and_looping_structures/ChallengeProject/Own/Own.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

019_branching_and_looping_structures/ChallengeProject/Own/Program.cs

@@ -0,0 +1,276 @@
+int max_pets = 8;
+bool exit = false;
+string? selection;
+string separator = "+-------------------------------------" +
+                   "--------------------------------------+";
+string main_menu = @"
+    1. List all of our current pet information.
+    2. Assign values to the ourAnimals array fields.
+    3. Ensure animal ages and physical descriptions are complete.
+    4. Ensure animal nicknames and personality descriptions are complete.
+    5. Edit an animal's age.
+    6. Edit an animal's personality description.
+    7. Display all cats with a specified characteristic.
+    8. Display all dogs with a specified characteristic.
+
+  Enter menu item selection or type 'Exit' to exit the program
+";
+string[] description = {
+    "big sized female golden colored weighing about 20 pounds. housebroken.",
+    "large dark-brown male siver back weighing about 15 pounds. housebroken.",
+    "small white female weighing about 8 pounds. translucid at sun.",
+    "medium size male. fluorescent at night.",
+};
+string[] personality = {
+    "friendly",
+    "loves to have his ears rubbed at any time! loves to lean-in.",
+    "loves to have her belly rubbed. gives lots of kisses.",
+    "sauvage and lovelly.",
+};
+string[] options = { "1", "2", "3", "4", "5", "6", "7", "8", "exit" };
+string[] nickname = { "lola", "loki", "fuzz", "boby", "gogo", "besti" };
+string[] species = { "cat", "dog", "bee", "pig" };
+string[] abcd = { "a", "b", "c", "d" };
+int[] nums = { 1, 2, 3, 4, 5, 6, 7, 8 };
+string[,] our_animals = new string[max_pets, 6];
+Random rand = new Random();
+
+var clear = Console.Clear;
+
+void print(string text, bool new_line = true) {
+    if (new_line) {
+        Console.WriteLine(text);
+    } else {
+        Console.Write(text);
+    }
+}
+
+string rand_str(string[] choices) {
+    int indx = rand.Next(choices.Length);
+    return choices[indx];
+}
+
+int rand_int(int[] choices) {
+    int indx = rand.Next(choices.Length);
+    return choices[indx];
+}
+
+void populate_animals_array() {
+    for (int i = 0; i < max_pets - 4; i++) {
+        bool uniq_id = false;
+        our_animals[i, 0] = rand_str(species);
+        while (!uniq_id) {
+            bool check = true;
+            string id = $"{rand_str(abcd)}{rand_int(nums)}";
+            for (int j = 0; j < max_pets - 4; j++) {
+                if (!string.IsNullOrEmpty(our_animals[j, 1]) && our_animals[j, 1] == id) {
+                    uniq_id = false;
+                    check = false;
+                    break;
+                }
+            }
+            if (check) {
+                our_animals[i, 1] = id;
+                uniq_id = true;
+            }
+        }
+        our_animals[i, 2] = rand_str(description);
+        our_animals[i, 3] = $"{rand_int(nums)}";
+        our_animals[i, 4] = rand_str(personality);
+        our_animals[i, 5] = rand_str(nickname);
+    }
+}
+
+void press_enter() {
+    print("\n\tPress 'Enter' to continue", false);
+    Console.ReadLine();
+}
+
+void print_pets(string[,] animals) {
+    clear();
+    print(separator);
+    for (int j = 0; j < animals.GetLength(0); j++) {
+        string[] animal = new string[6];
+        for (int k = 0; k < animals.GetLength(1); k++) {
+            animal[k] = animals[j, k];
+        }
+        print_pet(animal);
+    }
+}
+
+void print_pet(string[] pet) {
+    if (!string.IsNullOrEmpty(pet[1])) {
+        string id = pet[1];
+        string name = pet[5];
+        string specie = pet[0];
+        int age = Int32.Parse(pet[3].ToString());
+        string year_word = age > 1 ? "years" : "year";
+        string desc = pet[2];
+        string perso = pet[4];
+        print($@"    ID: {id} SPECIE: {specie}
+    NAME: {name} AGE: {age} {year_word}
+    DESCRIPTION: {desc}
+    PERSONALITY: {perso}
+{separator}");
+    }
+}
+
+int availability(string[,] animals) {
+    int pet_count = 0;
+    for (int j = 0; j < animals.GetLength(0); j++) {
+        if (!string.IsNullOrEmpty(animals[j, 1])) {
+            pet_count++;
+        }
+    }
+    int slots = max_pets - pet_count;
+    return slots;
+}
+
+string get_input(string text = "Please enter your text: ", bool integer = false) {
+    bool invalid = true;
+    while (invalid) {
+        print(text, false);
+        string? usr_in = Console.ReadLine();
+        if (!string.IsNullOrEmpty(usr_in) && usr_in.Trim() != "") {
+            if (integer) {
+                string resp = usr_in.Trim();
+                int temp_int;
+                if (int.TryParse(resp, out temp_int)) {
+                    print($"Opción 1: {temp_int}");
+                    return resp;
+                }
+            } else {
+                return usr_in.Trim();
+            }
+        }
+    }
+    return "";
+}
+
+void add_new_pet(string[,] animals, int slots) {
+    int at_indx = max_pets - slots;
+    string id = $"{rand_str(abcd)}{rand_int(nums)}";
+    string specie = get_input("Enter pet specie: ");
+    string name = get_input("Enter the pet name (? if unknown): ");
+    int age = Int32.Parse(get_input("Enter pet age (-1 if unknown): ", true));
+    string desc = get_input("Enter the physical description (? if unknown): ");
+    string perso = get_input("Enter pet personality (? if unknown): ");
+    //print($"Will be added at index: {at_indx}");
+    //print($"{id}\n{specie}\n{name}\n{age}\n{desc}\n{perso}");
+    animals[at_indx, 0] = specie;
+    animals[at_indx, 1] = id;
+    animals[at_indx, 2] = desc;
+    animals[at_indx, 3] = age.ToString();
+    animals[at_indx, 4] = perso;
+    animals[at_indx, 5] = name;
+}
+
+void ask_new_pet() {
+    clear();
+    print("Assign values to the ourAnimals array fields");
+    print(separator);
+    int slots = availability(our_animals);
+    print($"\nWe currently have {max_pets - slots} pets that need homes.");
+    print($"We can manage {slots} more.");
+    if (slots > 0) {
+        bool another = false;
+        do {
+            string resp = get_input("Do you want to enter info for another pet?: ");
+            bool invalid = true;
+            if (resp != "") {
+                while (invalid) {
+                    switch (resp) {
+                        case "y" or "yes":
+                            add_new_pet(our_animals, slots);
+                            resp = "";
+                            invalid = false;
+                            another = true;
+                            break;
+                        case "n" or "no":
+                            invalid = false;
+                            another = false;
+                            break;
+                        default:
+                            resp = get_input("Please enter [Y]es or [N]o: ");
+                            break;
+                    }
+                }
+            }
+            slots = availability(our_animals);
+        } while (another && slots > 0);
+        if (slots == 0) {
+            print("We have reached our limit on the number of pets that we can manage.");
+            press_enter();
+        }
+        press_enter();
+    } else {
+        press_enter();
+    }
+}
+
+void check_age_and_desc() {
+    int pet_count = max_pets - (availability(our_animals));
+}
+
+populate_animals_array();
+while (!exit) {
+    clear();
+    print(main_menu);
+    selection = Console.ReadLine();
+    if (selection != null && options.Contains(selection.ToLower())) {
+        selection = selection.ToLower();
+        switch (selection) {
+            case "1":
+                print_pets(our_animals);
+                press_enter();
+                break;
+            case "2":
+                ask_new_pet();
+                break;
+            case "3":
+                clear();
+                print("Ensure animal ages and physical descriptions are complete");
+                check_age_and_desc();
+                press_enter();
+                break;
+            case "4":
+                clear();
+                print("Ensure animal nicknames and personality descriptions are complete");
+                press_enter();
+                break;
+            case "5":
+                clear();
+                print("Edit an animal's age");
+                press_enter();
+                break;
+            case "6":
+                clear();
+                print("Edit an animal's personality description");
+                press_enter();
+                break;
+            case "7":
+                clear();
+                print("Display all cats with a specified characteristic");
+                press_enter();
+                break;
+            case "8":
+                clear();
+                print("Display all dogs with a specified characteristic");
+                press_enter();
+                break;
+            case "exit":
+                print("\n\tTerminating application\n");
+                exit = !exit;
+                break;
+            default:
+                print("\n\tPlease read the instructions");
+                press_enter();
+                break;
+        }
+    } else {
+        print("\n\tPlease read the instructions");
+        press_enter();
+    }
+}
+
+Environment.Exit(0);

019_branching_and_looping_structures/ChallengeProject/README.md

@@ -0,0 +1,2 @@
+# Challenge-project-branching-looping-CSharp
+Starter and Solution code for the Challenge project: "Develop conditional branching and looping structures in C#" from the Microsoft Learn collection "Getting started with C#"

019_branching_and_looping_structures/ChallengeProject/Starter/Program.cs

@@ -0,0 +1,334 @@
+using System;
+using System.IO;
+
+// the ourAnimals array will store the following: 
+string animalSpecies = "";
+string animalID = "";
+string animalAge = "";
+string animalPhysicalDescription = "";
+string animalPersonalityDescription = "";
+string animalNickname = "";
+
+// variables that support data entry
+int maxPets = 8;
+string? readResult;
+string menuSelection = "";
+int petCount = 0;
+string anotherPet = "y";
+bool validEntry = false;
+int petAge = 0;
+
+// array used to store runtime data, there is no persisted data
+string[,] ourAnimals = new string[maxPets, 6];
+
+// create some initial ourAnimals array entries
+for (int i = 0; i < maxPets; i++)
+{
+    switch (i)
+    {
+        case 0:
+            animalSpecies = "dog";
+            animalID = "d1";
+            animalAge = "2";
+            animalPhysicalDescription = "medium sized cream colored female golden retriever weighing about 65 pounds. housebroken.";
+            animalPersonalityDescription = "loves to have her belly rubbed and likes to chase her tail. gives lots of kisses.";
+            animalNickname = "lola";
+            break;
+
+        case 1:
+            animalSpecies = "dog";
+            animalID = "d2";
+            animalAge = "9";
+            animalPhysicalDescription = "large reddish-brown male golden retriever weighing about 85 pounds. housebroken.";
+            animalPersonalityDescription = "loves to have his ears rubbed when he greets you at the door, or at any time! loves to lean-in and give doggy hugs.";
+            animalNickname = "loki";
+            break;
+
+        case 2:
+            animalSpecies = "cat";
+            animalID = "c3";
+            animalAge = "1";
+            animalPhysicalDescription = "small white female weighing about 8 pounds. litter box trained.";
+            animalPersonalityDescription = "friendly";
+            animalNickname = "Puss";
+            break;
+
+        case 3:
+            animalSpecies = "cat";
+            animalID = "c4";
+            animalAge = "?";
+            animalPhysicalDescription = "";
+            animalPersonalityDescription = "";
+            animalNickname = "";
+
+            break;
+
+        default:
+            animalSpecies = "";
+            animalID = "";
+            animalAge = "";
+            animalPhysicalDescription = "";
+            animalPersonalityDescription = "";
+            animalNickname = "";
+            break;
+
+    }
+
+    ourAnimals[i, 0] = "ID #: " + animalID;
+    ourAnimals[i, 1] = "Species: " + animalSpecies;
+    ourAnimals[i, 2] = "Age: " + animalAge;
+    ourAnimals[i, 3] = "Nickname: " + animalNickname;
+    ourAnimals[i, 4] = "Physical description: " + animalPhysicalDescription;
+    ourAnimals[i, 5] = "Personality: " + animalPersonalityDescription;
+}
+
+// display the top-level menu options
+do
+{
+    Console.Clear();
+
+    Console.WriteLine("Welcome to the Contoso PetFriends app. Your main menu options are:");
+    Console.WriteLine(" 1. List all of our current pet information");
+    Console.WriteLine(" 2. Add a new animal friend to the ourAnimals array");
+    Console.WriteLine(" 3. Ensure animal ages and physical descriptions are complete");
+    Console.WriteLine(" 4. Ensure animal nicknames and personality descriptions are complete");
+    Console.WriteLine(" 5. Edit an animal’s age");
+    Console.WriteLine(" 6. Edit an animal’s personality description");
+    Console.WriteLine(" 7. Display all cats with a specified characteristic");
+    Console.WriteLine(" 8. Display all dogs with a specified characteristic");
+    Console.WriteLine();
+    Console.WriteLine("Enter your selection number (or type Exit to exit the program)");
+
+    readResult = Console.ReadLine();
+    if (readResult != null)
+    {
+        menuSelection = readResult.ToLower();
+        // NOTE: We could put a do statement around the menuSelection entry to ensure a valid entry, but we
+        //  use a conditional statement below that only processes the valid entry values, so the do statement 
+        //  is not required here. 
+    }
+
+    // use switch-case to process the selected menu option
+    switch (menuSelection)
+    {
+        case "1":
+            // List all of our current pet information
+            for (int i = 0; i < maxPets; i++)
+            {
+                if (ourAnimals[i, 0] != "ID #: ")
+                {
+                    Console.WriteLine();
+                    for (int j = 0; j < 6; j++)
+                    {
+                        Console.WriteLine(ourAnimals[i, j].ToString());
+                    }
+                }
+            }
+            Console.WriteLine("\n\rPress the Enter key to continue");
+            readResult = Console.ReadLine();
+
+            break;
+
+        case "2":
+            // Add a new animal friend to the ourAnimals array
+            //
+            // The ourAnimals array contains
+            //    1. the species (cat or dog). a required field
+            //    2. the ID number - for example C17
+            //    3. the pet's age. can be blank at initial entry.
+            //    4. the pet's nickname. can be blank.
+            //    5. a description of the pet's physical appearance. can be blank.
+            //    6. a description of the pet's personality. can be blank.
+
+            anotherPet = "y";
+            petCount = 0;
+            for (int i = 0; i < maxPets; i++)
+            {
+                if (ourAnimals[i, 0] != "ID #: ")
+                {
+                    petCount += 1;
+                }
+            }
+
+            if (petCount < maxPets)
+            {
+                Console.WriteLine($"We currently have {petCount} pets that need homes. We can manage {(maxPets - petCount)} more.");
+            }
+
+            while (anotherPet == "y" && petCount < maxPets)
+            {
+                // get species (cat or dog) - string animalSpecies is a required field 
+                do
+                {
+                    Console.WriteLine("\n\rEnter 'dog' or 'cat' to begin a new entry");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalSpecies = readResult.ToLower();
+                        if (animalSpecies != "dog" && animalSpecies != "cat")
+                        {
+                            //Console.WriteLine($"You entered: {animalSpecies}.");
+                            validEntry = false;
+                        }
+                        else
+                        {
+                            validEntry = true;
+                        }
+                    }
+                } while (validEntry == false);
+
+                // build the animal the ID number - for example C1, C2, D3 (for Cat 1, Cat 2, Dog 3)
+                animalID = animalSpecies.Substring(0, 1) + (petCount + 1).ToString();
+
+                // get the pet's age. can be ? at initial entry.
+                do
+                {
+                    Console.WriteLine("Enter the pet's age or enter ? if unknown");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalAge = readResult;
+                        if (animalAge != "?")
+                        {
+                            validEntry = int.TryParse(animalAge, out petAge);
+                        }
+                        else
+                        {
+                            validEntry = true;
+                        }
+                    }
+                } while (validEntry == false);
+
+
+                // get a description of the pet's physical appearance - animalPhysicalDescription can be blank.
+                do
+                {
+                    Console.WriteLine("Enter a physical description of the pet (size, color, gender, weight, housebroken)");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalPhysicalDescription = readResult.ToLower();
+                        if (animalPhysicalDescription == "")
+                        {
+                            animalPhysicalDescription = "tbd";
+                        }
+                    }
+                } while (validEntry == false);
+
+
+                // get a description of the pet's personality - animalPersonalityDescription can be blank.
+                do
+                {
+                    Console.WriteLine("Enter a description of the pet's personality (likes or dislikes, tricks, energy level)");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalPersonalityDescription = readResult.ToLower();
+                        if (animalPersonalityDescription == "")
+                        {
+                            animalPersonalityDescription = "tbd";
+                        }
+                    }
+                } while (validEntry == false);
+
+
+                // get the pet's nickname. animalNickname can be blank.
+                do
+                {
+                    Console.WriteLine("Enter a nickname for the pet");
+                    readResult = Console.ReadLine();
+                    if (readResult != null)
+                    {
+                        animalNickname = readResult.ToLower();
+                        if (animalNickname == "")
+                        {
+                            animalNickname = "tbd";
+                        }
+                    }
+                } while (validEntry == false);
+
+                // store the pet information in the ourAnimals array (zero based)
+                ourAnimals[petCount, 0] = "ID #: " + animalID;
+                ourAnimals[petCount, 1] = "Species: " + animalSpecies;
+                ourAnimals[petCount, 2] = "Age: " + animalAge;
+                ourAnimals[petCount, 3] = "Nickname: " + animalNickname;
+                ourAnimals[petCount, 4] = "Physical description: " + animalPhysicalDescription;
+                ourAnimals[petCount, 5] = "Personality: " + animalPersonalityDescription;
+
+                // increment petCount (the array is zero-based, so we increment the counter after adding to the array)
+                petCount = petCount + 1;
+
+                // check maxPet limit
+                if (petCount < maxPets)
+                {
+                    // another pet?
+                    Console.WriteLine("Do you want to enter info for another pet (y/n)");
+                    do
+                    {
+                        readResult = Console.ReadLine();
+                        if (readResult != null)
+                        {
+                            anotherPet = readResult.ToLower();
+                        }
+
+                    } while (anotherPet != "y" && anotherPet != "n");
+                }
+                //NOTE: The value of anotherPet (either "y" or "n") is evaluated in the while statement expression - at the top of the while loop
+            }
+
+            if (petCount >= maxPets)
+            {
+                Console.WriteLine("We have reached our limit on the number of pets that we can manage.");
+                Console.WriteLine("Press the Enter key to continue.");
+                readResult = Console.ReadLine();
+            }
+
+            break;
+
+        case "3":
+            // Ensure animal ages and physical descriptions are complete
+            Console.WriteLine("Challenge Project - please check back soon to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        case "4":
+            // Ensure animal nicknames and personality descriptions are complete
+            Console.WriteLine("Challenge Project - please check back soon to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        case "5":
+            // Edit an animal’s age");
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        case "6":
+            // Edit an animal’s personality description");
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+        
+        case "7":
+            // Display all cats with a specified characteristic
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        case "8":
+            // Display all dogs with a specified characteristic
+            Console.WriteLine("UNDER CONSTRUCTION - please check back next month to see progress.");
+            Console.WriteLine("Press the Enter key to continue.");
+            readResult = Console.ReadLine();
+            break;
+
+        default:
+            break;
+    }
+
+} while (menuSelection != "exit");

019_branching_and_looping_structures/ChallengeProject/Starter/Starter.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>