c# - EF Core 为用户添加角色

Question

我想包含用户的角色列表。

var users = Users
                .Include(u => u.UserRoles)
                .ToList()

我遵循了许多建议来解决问题，但没有一个对我有用:

• EF Core 2.0 Identity - Adding navigation properties
• http://kontext.tech/docs/DotNetEssential/p/migrating-from-aspnet-core-1x-to-aspnet-core-20
• https://github.com/aspnet/EntityFrameworkCore/issues/9503

所以很可能其他人也处于同样的情况。

启动.cs

    services.AddIdentity<User, Role>()
        .AddEntityFrameworkStores<ApiDbContext>()
        .AddDefaultTokenProviders()
        ;//.AddUserStore<UserStore<User, Role, ApiDbContext, Guid>>()//, IdentityUserClaim<Guid>, UserRole, IdentityUserLogin<Guid>, IdentityUserToken<Guid>, IdentityRoleClaim<Guid>>>()
         //.AddRoleStore<RoleStore<Role, ApiDbContext, Guid>>();//, UserRole, IdentityRoleClaim < Guid >>> ();

[注意]:在评论中，有许多不同的尝试使迁移工作但没有成功

角色.cs

 public class Role : IdentityRole<Guid>
 {
        public virtual ICollection<UserRole> UserRoles { get; } = new List<UserRole>();
 }

用户.cs

public class User : IdentityUser<Guid>, IEntity
{
    public virtual ICollection<UserRole> UserRoles { get; } = new List<UserRole>();
}

UserRole.cs

public class UserRole : IdentityUserRole<Guid>
{
    public virtual User User { get; }
    public virtual Role Role { get; }
}

ApiDbContext.cs

public class ApiDbContext : IdentityDbContext<User, Role, Guid, IdentityUserClaim<Guid>, UserRole, IdentityUserLogin<Guid>, IdentityRoleClaim<Guid>, IdentityUserToken<Guid>>
{
        protected override void OnModelCreating(ModelBuilder builder)
    {
        builder.Entity<User>()
            .HasMany(e => e.UserRoles)
            .WithOne()
            .HasForeignKey(e => e.UserId)
            .IsRequired()
            .OnDelete(DeleteBehavior.Cascade);

        builder.Entity<UserRole>()
            .HasOne(e => e.User)
            .WithMany(e => e.UserRoles)
            .HasForeignKey(e => e.UserId);

        builder.Entity<UserRole>()
            .HasOne(e => e.Role)
            .WithMany(e => e.UserRoles)
            .HasForeignKey(e => e.RoleId);

        base.OnModelCreating(builder);
    }

每次我运行“Add-migration”时，无论遵循什么建议，我总是会:

        migrationBuilder.CreateTable(
            name: "AspNetUserRoles",
            columns: table => new
            {
                UserId = table.Column<Guid>(nullable: false),
                RoleId = table.Column<Guid>(nullable: false),
                RoleId1 = table.Column<Guid>(nullable: true),
                UserId1 = table.Column<Guid>(nullable: true)
            },
            constraints: table =>
            {
                table.PrimaryKey("PK_AspNetUserRoles", x => new { x.UserId, x.RoleId });
                table.ForeignKey(
                    name: "FK_AspNetUserRoles_AspNetRoles_RoleId",
                    column: x => x.RoleId,
                    principalTable: "AspNetRoles",
                    principalColumn: "Id",
                    onDelete: ReferentialAction.Cascade);
                table.ForeignKey(
                    name: "FK_AspNetUserRoles_AspNetRoles_RoleId1",
                    column: x => x.RoleId1,
                    principalTable: "AspNetRoles",
                    principalColumn: "Id",
                    onDelete: ReferentialAction.Restrict);
                table.ForeignKey(
                    name: "FK_AspNetUserRoles_AspNetUsers_UserId",
                    column: x => x.UserId,
                    principalTable: "AspNetUsers",
                    principalColumn: "Id",
                    onDelete: ReferentialAction.Cascade);
                table.ForeignKey(
                    name: "FK_AspNetUserRoles_AspNetUsers_UserId1",
                    column: x => x.UserId1,
                    principalTable: "AspNetUsers",
                    principalColumn: "Id",
                    onDelete: ReferentialAction.Restrict);
            });

Role1 和 User1 不应该在那里。

我正在使用:

<PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="2.0.2" />

有人知道如何解决这个问题吗？

Answer 1

尝试将 setter 添加到 UserRole 的属性中。

public class UserRole : IdentityUserRole<Guid>
{
    public virtual User User { get; set; }
    public virtual Role Role { get; set; }
}

如果您需要只读它，您可以添加一个私有(private)构造函数。

public class UserRole : IdentityUserRole<Guid>
{
    private User _user;
    private Role _role;

    private UserRole()
    {
    }

    public UserRole(User user, Role role)
    {
        _user = user;
        _role = role;
    }

    public virtual User User => _user;
    public virtual Role Role => _role;
}

但是您需要在 dbcontext 中配置私有(private)字段。

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<UserRole>().Property(u => u.User).HasField("_user");
    modelBuilder.Entity<UserRole>().Property(u => u.Role).HasField("_role");
}