Introduction to Razor Pages

Razor Pages is a page-based model for building web apps in ASP.NET Core.

Page Structure

A Razor Page consists of two files:

1. .cshtml - The view template
2. .cshtml.cs - The page model (code-behind)

// ContactModel.cshtml.cs
public class ContactModel : PageModel
{
    [BindProperty]
    public Contact Contact { get; set; }

    public async Task<IActionResult> OnPostAsync()
    {
        if (!ModelState.IsValid)
        {
            return Page();
        }

        // Save the contact...
        return RedirectToPage("./Success");
    }
}

// Contact.cshtml
@page
@model ContactModel
<h1>Contact Us</h1>
<form method="post">
    <div>
        <label asp-for="Contact.Name"></label>
        <input asp-for="Contact.Name" />
    </div>
    <div>
        <label asp-for="Contact.Email"></label>
        <input asp-for="Contact.Email" />
    </div>
    <button type="submit">Send</button>
</form>

Key Concepts

1. Page Model
   • Handles page logic
   • Properties for view data
   • Event handlers for HTTP methods
2. Handler Methods
   • OnGet() - Handle GET requests
   • OnPost() - Handle POST requests
   • OnPutAsync() - Handle PUT requests
3. Model Binding
   • Automatic property binding
   • Form data mapping
   • Query string parameters