Getting this error using Entity Framework Navigation Properties - entity-framework

Question

I am getting this error
The entity type
'Microsoft.AspNet.Identity.EntityFramework.IdentityUserRole' to which
the navigation property 'Roles' refers does not derive from the type
'SafeWare.Models.ApplicationUserRole' on which the inverse navigation
property 'User' is declared.
while calling
bool ret = _userManager.Users.SingleOrDefault(x => x.UserName == userName) != null;
This function tests to see is a User exists.
Here are my objects:
public class ApplicationRole : IdentityRole
{
public ApplicationRole() : base()
{
Users = new HashSet<ApplicationUserRole>();
}
public ApplicationRole(string name, string description) : base(name)
{
this.Description = description;
}
public virtual string Description { get; set; }
[InverseProperty("Role")]
[DisplayName("Users")]
public new virtual ICollection<ApplicationUserRole> Users { get; set; }
}
public class ApplicationUser : IdentityUser
{
public async Task<ClaimsIdentity> GenerateUserIdentityAsync(UserManager<ApplicationUser> manager)
{
// Note the authenticationType must match the one defined in CookieAuthenticationOptions.AuthenticationType
var userIdentity = await manager.CreateIdentityAsync(this, DefaultAuthenticationTypes.ApplicationCookie);
// Add custom user claims here
return userIdentity;
}
public ApplicationUser()
{
FileUploads = new HashSet<FileUpload>();
Roles = new HashSet<ApplicationUserRole>();
}
[InverseProperty("User")]
[DisplayName("Roles")]
public new virtual ICollection<ApplicationUserRole> Roles { get; set; }
}
public class ApplicationUserRole : IdentityUserRole
{
public ApplicationUserRole()
{
}
[ForeignKey("Id")]
public virtual ApplicationUser User { get; set; }
[ForeignKey("Id")]
public virtual ApplicationRole Role { get; set; }
}
public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{
public ApplicationDbContext()
: base("DefaultConnection", throwIfV1Schema: false)
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Entity<ApplicationUser>().ToTable("AspNetUsers");
modelBuilder.Entity<ApplicationRole>().HasKey<string>(r => r.Id).ToTable("AspNetRoles");
modelBuilder.Entity<ApplicationUserRole>().HasKey(r => new { r.UserId, r.RoleId }).ToTable("AspNetUserRoles");
modelBuilder.Entity<ApplicationUser>().HasMany(u => u.Roles).WithRequired().HasForeignKey(ur => ur.User).WillCascadeOnDelete(value: false);
modelBuilder.Entity<ApplicationRole>().HasMany(r => r.Users).WithRequired().HasForeignKey(ur => ur.Role).WillCascadeOnDelete(value: false);
//modelBuilder.Entity<ApplicationRole>().HasMany<ApplicationUserRole>((ApplicationRole u) => u.Users);
//modelBuilder.Entity<ApplicationUser>().HasMany<ApplicationUserRole>((ApplicationUser u) => u.Roles);
}
}
Please help!

Answer 1

The Inverse Properties attribute i.e. [InverseProperty("User")] and [InverseProperty("Role")] declare properties of type ICollection<ApplicationUserRole> but they point to properties of type ApplicationUser and ApplicationRole on the ApplicationUserRole class.
For example ,
[InverseProperty("User")]
[DisplayName("Roles")]
public new virtual ICollection<ApplicationUserRole> Roles { get; set; }
points to
[ForeignKey("Id")]
public virtual ApplicationUser User { get; set; }
which is of type ApplicationUser and not ApplicationUserRole
Have you tried removing the InverseProperty attribute?
Should it not be public override ICollection<ApplicationUserRole> Roles { get; } if you are looking to override the base Roles method.
Personally I would pass the type to the base class IdentityUser<TKey, TLogin, TRole, TClaim> : IUser<TKey> instead of overriding the Roles method in IdentityUser method
e.g. ApplicationUser : IdentityUser<TKey, TLogin, ApplicationUserRole, TClaim>
The same principle can be applied to other identity models e.g. ApplicationRole