Loading...

OBJECT ORIENTED PROGRAMMING  

>

LEARNING OUTCOME 3

VISUAL STUDIO IDE

VISUAL STUDIO IDE : Your Development Workstation

Visual Studio (VS) is a powerful Integrated Development Environment (IDE) from Microsoft, specifically designed for building applications on the Windows platform. It offers a comprehensive set of tools and functionalities to streamline the development process. Here's a breakdown of its key components:

  1. MENUS :
    • The menus provide access to a wide range of commands for various development tasks. They are typically located at the top of the main window. Here's a glimpse into some common menus:
      • File : Used for managing project files, creating new projects, opening existing projects, saving your work, and closing projects.
      • Edit : Offers functionalities for editing code, such as copy, paste, undo, redo, find, and replace.
      • View : Controls the layout of the IDE window, including showing or hiding toolbars, windows like the Solution Explorer and Properties window, and zooming in and out of code.
      • Project : Provides options for managing project properties, adding references to external libraries, and configuring build settings.
      • Build : Initiates the build process to compile your code into an executable or library.
      • Debug : Offers tools for debugging your application, including setting breakpoints, stepping through code execution line by line, and examining variables.
      • Team : Used for collaborating with other developers on projects using version control systems (like Git).
      • Test : Provides tools for writing and running unit tests for your code.
      • Window : Allows you to arrange and manage the layout of various windows within the IDE.
      • Help : Provides access to documentation, tutorials, and other resources for learning Visual Studio and the programming languages it supports.
  2. TOOLBARS :
    • Toolbars provide quick access to frequently used commands through icons or buttons. You can customize toolbars to display the commands you need most readily available.
  3. SOLUTION EXPLORER :
    • This window displays a hierarchical view of your project's structure, including source code files, resource files, libraries, and other assets. It allows you to navigate through your project files, add new items, and manage project dependencies.
  4. Code Editor :
    • The heart of the IDE where you write and edit your code. Visual Studio offers advanced code editing features like syntax highlighting, code completion, code snippets, and refactoring tools.
  5. Properties Window :
    • This window displays the properties of the currently selected item in the code editor or Solution Explorer. You can use it to modify properties of controls, variables, and other elements in your project.
  6. Output Window :
    • Shows the output of the build process, including any errors or warnings encountered during compilation. It can also display debug information during debugging sessions.
  7. Error List :
    • Lists any errors or warnings detected in your code during compilation or code analysis. This helps you identify and fix potential problems in your code.
  8. Command Window :
    • Allows you to execute commands directly through a text-based interface. You can use it to automate tasks or run external tools from within Visual Studio.

Additional Notes :

VISUAL STUDIO IDE: Weighing the Pros and Cons

VISUAL STUDIO IDE : A popular IDE, but like any tool, it has its own set of advantages and disadvantages. Here's a balanced breakdown to help you decide if it's the right fit for your development needs:

ADVANTAGES :

DISADVANTAGES :

Visual Studio is a powerful and feature-rich IDE that caters well to Windows development and Microsoft technologies. Its extensive functionalities, integration capabilities, and vast community resources make it a popular choice for many developers. However, the cost (for some editions), Windows-centric focus, and potential learning curve are factors to consider. Evaluate your project requirements, development environment, and budget to determine if Visual Studio is the best IDE for you. If you're open to exploring alternatives, consider options like Visual Studio Code (a free, cross-platform code editor from Microsoft), or JetBrains IDEs (like IntelliJ IDEA or PyCharm) that offer similar functionalities for different programming languages and platforms.

EVENT-DRIVEN PROGRAMMING (EDP)

EVENT-DRIVEN PROGRAMMING (EDP) : In C#, event-driven programming (EDP) is a powerful paradigm that revolves around handling events (signals indicating something has happened) and responding to them with appropriate actions. Here's a breakdown of the key concepts:

  1. EVENTS :
    • Events are signals that something noteworthy has occurred within an object. They act as a notification mechanism for other parts of your program to react to these occurrences.
    • Events are typically declared within a class using the event keyword followed by a delegate type.
      • C#
		public class Button
		{
		 public event EventHandler Click; // Event declaration using EventHandler delegate
		}
    • In this example, the Button class declares an event called Click. This event will be triggered when the button is clicked, notifying any interested parties (event handlers) that have subscribed to this event.
  2. DELEGATES :
    • Delegates are a type-safe mechanism for defining function pointers. They specify the signature (return type and parameter list) of a group of methods that can be invoked when the event is raised.
    • Classes can subscribe to events by providing methods that match the delegate signature. These methods become the event handlers that will be executed when the event occurs.
      • C#
		public delegate void EventHandler(object sender, EventArgs e); // Delegate definition
    • The EventHandler delegate defines the signature for methods that can handle the Click event. It takes two arguments:
      • sender : The object that raised the event (usually the button in this case).
      • e : An optional argument that can provide additional information about the event (often an EventArgs object or a derived class).
  3. EVENT-DRIVEN PROGRAMMING (EDP) :
    • EDP is a programming style where the flow of control is determined by events. Objects raise events when something significant happens, and other objects (event handlers) are notified and can take appropriate actions in response.
    • This approach promotes loose coupling between objects. Event publishers (objects raising events) don't need to know who or how many objects are subscribed to their events. Similarly, event subscribers (objects handling events) don't need to know how or when events are raised. They simply define the methods (event handlers) to respond to the notification.

BENEFITS OF EVENT-DRIVEN PROGRAMMING :

Example of Event-Driven Programming :

Consider a simple button click scenario:

C#
		public class Button
		{
		 public event EventHandler Click;
		 public void OnClick()
		 {
		 // Simulate button click logic
		 Click?.Invoke(this, EventArgs.Empty); // Raise the Click event
		 }
		}
		public class Form
		{
		 private Button myButton;
		 public Form()
		 {
		 myButton = new Button();
		 myButton.Click += MyButton_Click; // Subscribe to the Click event
		 }
		 private void MyButton_Click(object sender, EventArgs e)
		 {
		 Console.WriteLine("Button clicked!");
		 }
		}

In this example:

Event-driven programming is a cornerstone of many modern C# applications, enabling you to create responsive, maintainable, and well-structured systems.

EVENT PUBLISHING, SUBSCRIBING, AND EVENT HANDLING

EVENT PUBLISHING :

EVENT SUBSCRIBING :

EVENT HANDLING :

#

BENEFITS OF EVENT-DRIVEN PROGRAMMING:

Event-driven programming is a powerful paradigm in C# that allows for creating well-structured, maintainable, and responsive applications. By effectively utilizing event publishing, subscribing, and handling, you can design applications that react appropriately to various events and user interactions.

Creating a GUI for applications that responds to user events in C# with Windows Forms (.NET Framework).

PROCESSES:

  1. Create a New Windows Forms Application:
      Creating new project
    • Open Visual Studio and choose "Create a new project."
    • Select "Windows Forms App (.NET Framework)" under Visual Studio templates and name your project.
      • Writing Event Handler Code
  2. Design the User Interface (UI):
      Designing UI

      Designing UI

      Designing UI

    • The Visual Studio designer allows you to drag and drop UI elements like buttons, text boxes, labels, and panels onto the form.
    • Double-click on elements to set their properties like text, size, and location.
    • DRAG THE BUTTON AND LABEL FROM HERE TO HERE
  3. Write Event Handler Code:
      Designing UI
    • In the code window (usually on the right side), you'll find code for the form class (e.g., Form1.cs).
    • Double-click on a UI element in the designer to navigate to its event handler method (e.g., a button click event handler).
    • Inside the event handler, write the code that should be executed when the user interacts with the element (e.g., displaying a message when a button is clicked).
  4. Compile and Run the Application:
    • Press F5 or go to Debug > Start Without Debugging to run your application and see the UI elements and their functionalities.

Navigation and Element Management:

Font Changes and Design Principles:

Code Snippet (Example Button Click Event Handler):


public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    private void button1_Click(object sender, EventArgs e)
    {
        // Code to execute when button1 is clicked
        MessageBox.Show("Button clicked!", "Message");
    }
}

Explanation:

Additional Tips:

INTEGRATING SOURCE CONTROL WITH VISUAL STUDIO: Branching, Merging, and Version Control

Visual Studio offers seamless integration with various source control systems (SCSs) like Git to effectively manage your project's code versions, collaborate with other developers, and track changes.

Here's an overview of this process, including branching, merging, and version control:

1. Setting Up Source Control:

2. Version Control:

3. Branching:

4. Merging:

BENEFITS OF USING SOURCE CONTROL:

Steps to Integrate Source Control (Example with Git):

  1. Install Git: Download and install Git for your operating system.
  2. Initialize a Git Repository: Open a command prompt or terminal in your project directory and run git init. This creates a hidden .git folder where Git stores version control data.
  3. Connect Visual Studio to the Repository: Follow the steps mentioned earlier under "Setting Up Source Control" to connect your Visual Studio project to the Git repository (local or remote on a platform like GitHub).

Branching and Merging in Visual Studio:

  1. Create a Branch:
    • In Team Explorer, navigate to the "Git" tab.
    • Under "Branches," right-click on the main branch (usually named master or main) and select "New Branch..."
    • Give your new branch a descriptive name.
  2. Work on the Branch:
    • Make your code changes in the new branch.
    • Commit your changes regularly with meaningful commit messages.
  3. Merge the Branch:
    • Once you're ready to integrate your changes back to the main branch, navigate to the "Git" tab in Team Explorer.
    • Under "Branches," locate your branch and right-click on it.
    • Select "Merge into main" (or the appropriate branch name).
    • Visual Studio will guide you through the merge process, highlighting any conflicts that need to be resolved manually.

PROJECT TYPES AND TEMPLATES IN VISUAL STUDIO: Building C# Console Applications

Visual Studio offers various project types and templates to kickstart your development process efficiently.

Here's a breakdown of project types and the structure of console applications in C#:

Project Types:

Visual Studio provides a variety of project types tailored to different development needs. Here are some common ones:

The specific project type you choose depends on the type of application you're building.

CONSOLE APPLICATION STRUCTURE:

When you create a new Console App (.NET Framework) project in Visual Studio, it provides a basic structure that you can build upon:

Example Console Application Structure:


MyConsoleApp/
    - MyConsoleApp.csproj // Project configuration file
    - Program.cs // Main program file with the Main method
    - (OtherClassFiles.cs) // Optional additional class files

Key Concepts in Console Applications:

Benefits of Using Project Types and Templates:

WINDOWS FORMS APPLICATION PROJECT STRUCTURE IN C#

When you create a new Windows Forms Application project in Visual Studio using C#, it provides a fundamental structure that you can expand upon to build your application.

Here's a breakdown of the key components:

1. Project File (.csproj):

2. Form Files (.cs and .Designer.cs):

3. Resource Files (Optional):

4. Additional Class Files (Optional):

Example Project Structure:


MyWinFormsApp/
    - MyWinFormsApp.csproj // Project configuration file
    - Form1.cs // C# code for the main form
    - Form1.Designer.cs // Auto-generated code for Form1 visual elements
    - (OtherFormFiles.cs) // Optional additional form class files
    - Resources/ // Optional folder for resource files (images, icons, etc.)
        - MyImage.jpg // Example image resource
    - (OtherClassFiles.cs) // Optional additional class files for application logic
    - (App.config) // Optional configuration file (for application settings)

Key Considerations:

That was a general structure, and your project might have additional files or folders depending on its specific requirements. As your application grows, you can further organize the code using namespaces, folders, and proper naming conventions for better maintainability. By understanding this core structure, you can effectively build well-organized and user-friendly Windows Forms applications in C#.

Detailed guide on creating a WPF application project in C# using Visual Studio:

1. OPEN VISUAL STUDIO AND CREATE A NEW PROJECT:

2. UNDERSTANDING THE PROJECT STRUCTURE:

Visual Studio creates a basic project structure with essential files:

new

3. Designing the User Interface (UI) with XAML:

4. WRITING CODE-BEHIND LOGIC (MAINWINDOW.CS):

This is the part called “CODE BEHIND” SO this is where you change your Label text, For example, let’s change “Username” to “NotUserNameSacker”

new

5. BUILDING AND RUNNING THE APPLICATION:

Additional Tips:

Learning Resources:

ELEMENTS OF A C# PROGRAM

USING BREAKPOINTS AND STEPPING THROUGH CODE IN A DEBUGGER

TESTING C# PROGRAMS WITH UNIT TESTING FRAMEWORKS: NUNIT, MSTEST, AND XUNIT

WRITING UNIT TESTS (XUNIT)

Here's a basic example demonstrating unit testing a simple Calculator class with XUnit:

C#
public class CalculatorTests
{
    [Fact]
    public void Add_TwoPositives_ReturnsSum()
    {
        // Arrange
        int num1 = 5;
        int num2 = 3;
        var calculator = new Calculator();
        // Act
        int result = calculator.Add(num1, num2);
        // Assert
        Assert.Equal(8, result);
    }
}

Running Unit Tests

Benefits of Unit Testing Frameworks

Remember: Unit testing is an ongoing process. As your code evolves, continuously write and update unit tests to ensure your application's overall quality. By leveraging these frameworks effectively, you can write robust and well-tested C# programs.

MOCKING OBJECTS AND DEPENDENCIES WITH MOQ IN C# UNIT TESTING

Mocking frameworks like Moq play a crucial role in effective unit testing. They allow you to create simulated objects (mocks) that stand in for real dependencies in your code. This enables you to isolate and test the functionality of your unit (class, function) without relying on external systems or complex interactions.

Why Use Mocking?

Moq FRAMEWORK

Moq is a popular open-source mocking framework for C#. It offers a clean and expressive syntax to create mocks and define their behavior.

Mocking Example with Moq

Here's a scenario where you want to test a CustomerService class that depends on a CustomerRepository class to retrieve customer data:

Without Mocking (Problematic)

C#
public class CustomerServiceTests
{
    [Test]
    public void GetCustomerById_ValidId_ReturnsCustomer()
    {
        int customerId = 1;
        var customerRepository = new CustomerRepository(); // Real repository dependency
        var customerService = new CustomerService(customerRepository);
        var customer = customerService.GetCustomerById(customerId);
        // Assert the retrieved customer data
    }
}

Mocking with Moq (Better Approach)

C#
public class CustomerServiceTests
{
    [Test]
    public void GetCustomerById_ValidId_ReturnsCustomer()
    {
        int customerId = 1;
        var mockCustomerRepository = new Mock(); // Mock interface
        // Define mock behavior: return a sample customer for this test
        mockCustomerRepository.Setup(repo =>
            repo.GetCustomerById(customerId))
            .Returns(new Customer { Id = 1, Name = "Sean Dhlamini" });
        var customerService = new CustomerService(mockCustomerRepository.Object);
        var customer = customerService.GetCustomerById(customerId);
        // Assert the retrieved customer data (should be the sample customer)
    }
}

Benefits of Mocking

Moq Features

Beyond Moq

While Moq is a popular choice, other mocking frameworks like JustMock, RhinoMocks, and FakeItEasy are also available, offering similar functionalities.

CONCLUSION

Mocking is a valuable technique for unit testing C# applications. By leveraging frameworks like Moq, you can create more efficient, isolated, and well-controlled unit tests, leading to increased code quality and confidence in your software.

TEST-DRIVEN DEVELOPMENT (TDD) IN C#

Test-Driven Development (TDD) is a software development approach where you write tests before writing the actual code. This flips the traditional development process on its head and offers several advantages for building robust and maintainable C# applications.

TDD Workflow

  1. Point noted: Red: Start by defining a failing unit test for the functionality you want to implement. This test outlines the expected behavior of your code.
  2. Point noted: Green: Write the minimum amount of code necessary to make the failing test pass. Focus on implementing the core logic to satisfy the test requirements.
  3. Point noted: Refactor: With the test passing, refactor and improve your code without breaking the test. This ensures your code remains clean, efficient, and well-structured.

Benefits of TDD

Challenges of TDD

Getting Started with TDD in C#

End of Outcome Quiz

1 of 20

    Quiz Score

    Percentage: 0%

    Answered Questions: 0

    Correct Answers: 0

    Faults:

      Next Chapter →

      © ExamSidemann 2025