ASP.NET CORE 中的 controller 中未处理的页面操作

Question

I created controller and views with default utility in VS that generate code.

When I click on create button on Create page I always have exception and breakpoints in Create method not working. I try change some handlers, change arguments or change asp-action for form but I couldn't enter to Create handler.

How I can fix it?

Create page

@model BulkyBook.Models.Category

@{
    ViewData["Title"] = "Create";
    Layout = "~/Views/Shared/_Layout.cshtml";
}

<h1>Create</h1>

<h4>Category</h4>
<hr />
<div class="row">
    <div class="col-md-4">
        <form asp-action="Create">
            <div asp-validation-summary="ModelOnly" class="text-danger"></div>
            <div class="form-group">
                <label asp-for="Name" class="control-label"></label>
                <input asp-for="Name" class="form-control" />
                <span asp-validation-for="Name" class="text-danger"></span>
            </div>
            <div class="form-group">
                <input type="submit" value="Create" class="btn btn-primary" />
            </div>
        </form>
    </div>
</div>

<div>
    <a asp-action="Index">Back to List</a>
</div>

@section Scripts {
    @{await Html.RenderPartialAsync("_ValidationScriptsPartial");}
}

Part of controller core that not working

using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using BulkyBook.DataAccess.Data;
using BulkyBook.Models;

namespace BulkyBook.Areas.Admin.Controllers
{
    [Area("Admin")]
    public class CategoriesController : Controller
    {
        private readonly ApplicationDbContext _context;

        public CategoriesController(ApplicationDbContext context)
        {
            _context = context;
        }

        // GET: Admin/Categories
        public async Task<IActionResult> Index()
        {
            return View(await _context.Categories.ToListAsync());
        }

        // GET: Admin/Categories/Create
        public IActionResult Create()
        {
            return View();
        }

        // POST: Admin/Categories/Create
        // To protect from overposting attacks, enable the specific properties you want to bind to.
        // For more details, see http://go.microsoft.com/fwlink/?LinkId=317598.
        [HttpPost]
        [ValidateAntiForgeryToken]
        public async Task<IActionResult> Create([Bind("Id,Name")] Category category)
        {
            if (ModelState.IsValid)
            {
                _context.Add(category);
                await _context.SaveChangesAsync();
                return RedirectToAction(nameof(Index));
            }
            return View(category);
        }
    }
}

Exception

Answer 1

Can you describe what kind of exception that you are getting when you clicking the C reate Button

Answer 2

When I click on create button on Create page I always have exception and breakpoints in Create method not working. I try change some handlers, change arguments or change asp-action for form but I couldn't enter to Create handler.

It seems that you create and use Areas feature in your project, please check if you create/copy _ViewImports.cshtml file with following code snippet to the appropriate view folder under areas, which could help make Tag Helpers available for your areas view(s).

@addTagHelper *, Microsoft.AspNetCore.Mvc.TagHelpers

For more information, please check this doc:

https://docs.microsoft.com/en-us/aspnet/core/mvc/controllers/areas?view=aspnetcore-5.0#_viewimportscshtml

Besides, if your view page Create is not in the same area, please explicitly asp-area="admin" for your form tag helper.

Answer 3

<form asp-action="Create" asp-area="Admin" method="post">

Please try above bold area.

And let me know if it's not work.