**Course Title:** Mastering C#: From Fundamentals to Advanced Programming **Section Title:** Building Web Applications with ASP.NET Core **Topic:** Introduction to web development with ASP.NET Core ### Overview Welcome to the world of web development with ASP.NET Core. In this topic, we will introduce you to the basics of web development using ASP.NET Core, a popular and widely-used framework for building web applications. By the end of this topic, you will have a solid understanding of what ASP.NET Core is, its features, and how to create a simple web application. ### What is ASP.NET Core? ASP.NET Core is a free and open-source web framework for building modern web applications. It is a cross-platform framework that can run on Windows, Linux, and macOS. ASP.NET Core provides a flexible and modular framework for building web applications, with a strong focus on scalability, performance, and security. ### Key Features of ASP.NET Core * **Cross-platform**: Runs on Windows, Linux, and macOS * **Open-source**: Free and open-source, with contributions from the community * **Modular**: Easy to update and replace individual components * **Scalable**: Designed to handle large volumes of traffic and data * **Secure**: Includes built-in security features and tools ### Creating a Simple ASP.NET Core Web Application To create a simple ASP.NET Core web application, follow these steps: 1. Install the .NET Core SDK from the official .NET website: [https://dotnet.microsoft.com/download](https://dotnet.microsoft.com/download) 2. Open a terminal or command prompt and navigate to the directory where you want to create your new project 3. Run the following command to create a new ASP.NET Core web application: `dotnet new web -o MyFirstWebApp` 4. Change into the directory of your new project: `cd MyFirstWebApp` 5. Run the following command to start the web server: `dotnet run` 6. Open a web browser and navigate to `http://localhost:5000` You should see a simple "Hello World" message displayed in your web browser. ### ASP.NET Core Project Structure A typical ASP.NET Core project consists of the following directories and files: * `Controllers`: contains the controller classes that handle HTTP requests and return HTTP responses * `Models`: contains the model classes that represent the data and business logic of your application * `Views`: contains the Razor views that generate the HTML for your application * `Startup.cs`: contains the code that configures the application and sets up the middleware pipeline ### Razor Pages Razor Pages is a feature of ASP.NET Core that allows you to create web pages using a simple syntax. Razor Pages are designed to be easy to use and provide a flexible way to create web pages. To create a new Razor page, add a new file to the `Pages` directory of your project. For example, you could create a new file called `HelloPage.cshtml` with the following code: ```csharp @page @model HelloPageModel <h1>Hello, World!</h1> ``` This code creates a new Razor page that displays a simple "Hello, World!" message. ### Conclusion In this topic, we introduced you to the basics of web development with ASP.NET Core. We covered the key features of ASP.NET Core and showed you how to create a simple web application using the .NET Core SDK. We also discussed the project structure of an ASP.NET Core project and introduced you to Razor Pages. ### What's Next? In the next topic, we will cover the MVC (Model-View-Controller) architecture, which is a powerful pattern for building web applications. We will discuss the different components of the MVC pattern and show you how to implement it in your ASP.NET Core applications. **Do you have any questions about this topic? Please leave a comment below or ask for help. We would be happy to assist you!**