ASP.NET Core Identity Razor Pages 用户编辑功能实现求助

It looks like your edit functionality is failing because you're mixing MVC patterns (like asp-action, asp-controller, and RedirectToAction) with Razor Pages, which has its own routing and model binding system. Let's walk through fixing this step by step.

First, Let's Identify the Key Issues in Your Current Code #

1. MVC-specific form attributes: Your Edit.cshtml uses asp-action and asp-controller, which don't apply to Razor Pages.
2. Missing user ID in redirect: When you redirect to the Edit page from OnPostChange, you aren't passing the user ID, so the Edit page can't load the target user.
3. Incorrect model binding: Your Edit page's fields aren't properly bound to the ApplicationUser model, and your OnPostEdit method tries to use standalone properties (like Email, Score) instead of a bound model.
4. Wrong redirect method: RedirectToAction is for MVC; Razor Pages uses RedirectToPage.

Step 1: Fix the Redirect from Index to Edit Page #

Update your OnPostChange method in Index.cshtml.cs to pass the user ID to the Edit page:

public async Task<IActionResult> OnPostChange(string id)
{
    var user = await _userManager.FindByIdAsync(id);
    if (user == null)
    {
        return NotFound();
    }
    // Pass the user ID to the Edit page via route parameters
    return RedirectToPage("Edit", new { id = id });
}

Step 2: Rewrite the Edit Page Model (Edit.cshtml.cs) #

We'll add an OnGetAsync method to load the user data when the page first loads, use [BindProperty] to bind the form data to the ApplicationUser model, and fix the update logic:

using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;

namespace YourProjectNamespace.Pages
{
    public class EditModel : PageModel
    {
        private readonly UserManager<ApplicationUser> _userManager;

        public EditModel(UserManager<ApplicationUser> userManager)
        {
            _userManager = userManager;
        }

        // Bind this property to the form data
        [BindProperty]
        public ApplicationUser ApUser { get; set; }

        // Load user data when the page is accessed via GET
        public async Task<IActionResult> OnGetAsync(string id)
        {
            if (id == null)
            {
                return NotFound();
            }

            ApUser = await _userManager.FindByIdAsync(id);
            if (ApUser == null)
            {
                return NotFound();
            }

            return Page();
        }

        // Handle form submission for edits
        public async Task<IActionResult> OnPostAsync()
        {
            if (!ModelState.IsValid)
            {
                return Page(); // Return to page if validation fails
            }

            // Get the existing user from the database to update
            var existingUser = await _userManager.FindByIdAsync(ApUser.Id);
            if (existingUser == null)
            {
                return NotFound();
            }

            // Update only the fields you need to change
            existingUser.Email = ApUser.Email;
            existingUser.UserName = ApUser.Email; // Keep UserName in sync with Email if required
            existingUser.Score = ApUser.Score;
            existingUser.Position = ApUser.Position;
            existingUser.Sequence = ApUser.Sequence;

            var result = await _userManager.UpdateAsync(existingUser);
            if (result.Succeeded)
            {
                // Redirect back to the user list page
                return RedirectToPage("Index");
            }

            // Add any Identity errors to the model state for display
            foreach (var error in result.Errors)
            {
                ModelState.AddModelError(string.Empty, error.Description);
            }

            // Return to the edit page to show errors
            return Page();
        }
    }
}

Step 3: Fix the Edit Page Markup (Edit.cshtml) #

Replace your existing form with Razor Pages-compatible markup, binding fields to the ApUser property and removing MVC-specific attributes:

@page "{id?}"
@model YourProjectNamespace.Pages.EditModel

<h1>Edit User</h1>

<form method="post">
    <div asp-validation-summary="All" class="text-danger"></div>

    <!-- Hidden field to retain the user ID -->
    <div class="form-group">
        <input type="hidden" asp-for="ApUser.Id" />
    </div>

    <div class="form-group">
        <label asp-for="ApUser.Email" class="control-label">Email</label>
        <input type="email" asp-for="ApUser.Email" class="form-control" />
        <span asp-validation-for="ApUser.Email" class="text-danger"></span>
    </div>

    <div class="form-group">
        <label asp-for="ApUser.Score" class="control-label">Score</label>
        <input type="number" asp-for="ApUser.Score" class="form-control" />
        <span asp-validation-for="ApUser.Score" class="text-danger"></span>
    </div>

    <div class="form-group">
        <label asp-for="ApUser.Position" class="control-label">Position</label>
        <input type="text" asp-for="ApUser.Position" class="form-control" />
        <span asp-validation-for="ApUser.Position" class="text-danger"></span>
    </div>

    <div class="form-group">
        <label asp-for="ApUser.Sequence" class="control-label">Sequence</label>
        <input type="number" asp-for="ApUser.Sequence" class="form-control" />
        <span asp-validation-for="ApUser.Sequence" class="text-danger"></span>
    </div>

    <div class="form-group">
        <input type="submit" value="Save" class="btn btn-primary" />
        <a asp-page="Index" class="btn btn-secondary">Cancel</a>
    </div>
</form>

Key Notes to Remember #

• Razor Pages Routing: The @page "{id?}" directive defines a route parameter for the user ID, making it accessible to the OnGetAsync method.
• Model Binding: The [BindProperty] attribute tells Razor Pages to map form data directly to the ApUser property.
• Identity Best Practices: Always fetch the existing user from the database before updating, rather than using the bound model directly—this ensures Identity's internal tracking works correctly.
• Validation: Use data annotations (like [Required], [EmailAddress]) on your ApplicationUser properties to enable client-side and server-side validation.

内容的提问来源于stack exchange，提问作者DVice