在ASP.NET MVC 5中删除角色

Question

I am trying to delete a Role from my database but it doesn't work , when I click the delete button, the system crashed and the error's message show me this :

It can't find the resource.

Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable. Review the following URL and make sure that it is spelled correctly.

Requested URL: / Roles / Delete

This is the method used in my RoleController.cs to Delete de Role:

public ActionResult Delete()
    {
        return View();
    }

 public ActionResult Delete(string RoleName)
    {
        var thisRole = context.Roles.Where(r => r.Name.Equals(RoleName, StringComparison.CurrentCultureIgnoreCase)).FirstOrDefault();

        context.Roles.Remove(thisRole);
        context.SaveChanges();
        return RedirectToAction("Index");
    }

My view is in my "Role" folder. This is the view used:

@{
    ViewBag.Title = "Index";
}

<h2>Roles Listing </h2>

@Html.ActionLink("Create New Role", "Create") | @Html.ActionLink("Manage User Role", "ManageUserRoles")
<hr />
<div>
    @foreach (var role in Model)
    {
        <p>
            <strong>@role.Name | </strong>
            <span onclick="return confirm('Are you sure to delete?')">
            <a href="/Roles/Delete?RoleName=@role.Name" class="delLink" style="color:red;">Delete</a>
            </span> |
            @Html.ActionLink("Edit", "Edit", new { roleName = @role.Name })
        </p>
    }
</div>

What can I do?

Edit (12/05/2015) :

My RouteConfig.cs is this:

    public class RouteConfig
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

        routes.MapRoute(
            name: "Default",
            url: "{controller}/{action}/{id}",
            defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
        );
    }
}

Answer 1

use HttpPost and HttpGet attribute for your actions

[HttpGet]
public ActionResult Delete()
{
    return View();
}

[HttpPost]
public ActionResult Delete(string RoleName)
{
    var thisRole = context.Roles.Where(r => r.Name.Equals(RoleName, StringComparison.CurrentCultureIgnoreCase)).FirstOrDefault();

    context.Roles.Remove(thisRole);
    context.SaveChanges();
    return RedirectToAction("Index");
}

The [HttpPost] attribute tells the routing engine to send any POST requests to that action method.

Answer 2

The error message suggests that your routing configuration is incorrect.

Have you created a route for it?

Looking at it, I'm guessing here.. Your url should actually be "Role/Delete" on a your hyperlink, as your trying to find it by "Roles/Delete" it probably wont find it.

Without seeing your RouteConfig.cs its hard to say.

EDIT.

Instead of this :-

<a href="/Roles/Delete?RoleName=@role.Name" class="delLink" style="color:red;">Delete</a>

Try this

 <a href='@Url.Action("Delete","Role", new { rolename = @Model.Name })' class="delLink" style="color:red;">Delete</a>