Viewing user roles show the role id instead of the role name

问题

I'm trying to configure role-based authorization in ASP.NET Identity. I want to make it so that Admin users can see a list of users and their roles (on the Index page) and change the roles of individual users (on an Edit page).

Here's my context:

modelBuilder.Entity<IdentityUser>()
    .HasKey<string>(k => k.Id)
    .ToTable("Users");
modelBuilder.Entity<IdentityUserRole>()
    .HasKey(r => new { r.RoleId, r.UserId })
    .ToTable("UserRoles");
modelBuilder.Entity<IdentityUserLogin>()
    .HasKey<string>(f => f.UserId)
    .ToTable("UserLogins");
modelBuilder.Entity<IdentityRole>()
    .ToTable("Roles");

My index action in UsersController.cs:

public ActionResult Index()
    {
        return View(db.Users.Include(i => i.Roles).ToList());
    }

Index view:

@model List<Microsoft.AspNet.Identity.EntityFramework.IdentityUser>

//stuff

    @foreach (var item in Model)
    {
        <tr class="index-item" data-href="@Url.Action("Details", "Users", new { id=item.Id })">
            <td>
                @Html.DisplayFor(modelItem => item.Email)
            </td>
            <td>
                @Html.DisplayFor(modelItem => item.Roles)">
            </td>
            <td class="index-links">
                //stuff
            </td>
        </tr>
    }
</table>

My Roles table:

My UserRoles table:

Based on these tables, the user has the "Viewer" role. However, instead of showing the Role name, the view shows the Role ID:

How do I make it show the Role name instead (in this case, "Viewer")?

回答1:

IdentityUserRole class have no navigation properties for IdentityUser and IdentityRole, just UserId and RoleId, its not that easy to get the roles of a user. So we need to use 2 db calls

var users = db.Users.Include(u => u.Roles);
var roles = db.Roles.Include(r => r.Users);

A ViewModel like this

public class UsersRolesViewModel 
{
     public List<ApplicationUser> Users { set; get; }
     public List<IdentityRole> Roles { set; get; }
}

and the in View

@foreach (var user in Model.Users)
{
    <tr class="index-item" data-href="@Url.Action("Details", "Users", new { id= user.Id })">
        <td>
            @user.Email
        </td>
        <td>
            @string.Join(",", roles.Where(r => r.Users.Any(u => u.UserId == user.Id)).Select(r => r.Name))
        </td>
        <td class="index-links">
                //stuff
        </td>
    </tr>
}

Edit

You can get all the data you want you with one query

var users = (from u in db.Users
             let query = (from ur in db.Set<IdentityUserRole>()
                          where ur.UserId.Equals(u.Id)
                          join r in db.Roles on ur.RoleId equals r.Id select r.Name)
                          select new UserDto() {User = u, Roles = query.ToList<string>()})
                         .ToList();

Using this simple model

public class UserDto
{
    public ApplicationUser User { set; get; }
    public List<string> Roles { set; get; } 
}

and the in View

  @foreach (var user in Model.Users)
  {
        var appUser = user.ApplicationUser;
        var roles = user.Roles;

        <tr class="index-item" data-href="@Url.Action("Details", "Users", new { id= appUser.Id })">
            <td>
                @appUser.Email
            </td>
            <td>
                @string.Join(",", roles)
            </td>
            <td class="index-links">
                    //stuff
            </td>
        </tr>
    }

回答2:

using System.Linq;
using System.Data;
using System.Data.Entity;

        var db = new ApplicationDbContext();
        var Users = db.Users.Include(u => u.Roles);

        foreach (var item in Users)
        {
            string UserName = item.UserName;
            string Roles = string.Join(",", item.Roles.Select(r=>r.RoleId).ToList());
        }

来源：https://stackoverflow.com/questions/37199545/viewing-user-roles-show-the-role-id-instead-of-the-role-name