ASP.NET Core Razor Pages

Razor Pages is a page-centric way to build Razor-based web UI with ASP.NET Core. It offers a simpler, more organized approach to building individual pages compared to traditional MVC.

What are Razor Pages?

A Razor Page is a set of files that includes:

• A Razor file (.cshtml): Contains the HTML markup and Razor syntax.
• A PageModel class (.cshtml.cs): Contains the code-behind logic, including handlers for HTTP requests and properties for the page.

The PageModel class inherits from PageModel, providing built-in functionality for request handling, model binding, and dependency injection.

Key Concepts

PageHandler Methods

Razor Pages uses a convention-based approach for handling HTTP requests. Methods named OnGet, OnPost, OnPut, etc., are automatically invoked based on the HTTP verb. You can also define specific handlers for different scenarios.

// Pages/Index.cshtml.cs
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;

public class IndexModel : PageModel
{
    public string Message { get; set; }

    public void OnGet()
    {
        Message = "Welcome to Razor Pages!";
    }

    public IActionResult OnPostSubmit(string name)
    {
        Message = $"Hello, {name}!";
        return Page();
    }
}
            

// Pages/Index.cshtml
@page
@model IndexModel
@{
    ViewData["Title"] = "Home page";
}

@Model.Message


    
    Submit

            

Model Binding

Razor Pages automatically binds data from incoming HTTP requests (form values, query strings, route data) to properties on your PageModel.

Dependency Injection

You can inject services into your PageModel class using standard ASP.NET Core dependency injection.

public class MyPageModel : PageModel
{
    private readonly IMyService _myService;

    public MyPageModel(IMyService myService)
    {
        _myService = myService;
    }

    public void OnGet()
    {
        ViewData["Data"] = _myService.GetData();
    }
}
            

Benefits of Razor Pages

• Simplicity: Easier to understand and develop for than traditional MVC for many scenarios.
• Organization: Keeps UI and logic for a specific page together.
• Code Sharing: Leverage existing Razor and ASP.NET Core features.
• Testability: PageModels are easily testable.

Getting Started

To create a new Razor Pages project:

1. Use the ASP.NET Core Web App template in Visual Studio or via the .NET CLI: dotnet new webapp -o MyRazorApp
2. Organize your pages within the Pages folder of your project.

Further Reading

Explore these related topics:

• ASP.NET Core Fundamentals
• ASP.NET Core MVC
• Razor Syntax