Entity Framework - How to configure the User Roles Many to Many Relationship - entity-framework

Question

Below is the definition of the User entity, there is a navigation property Roles
public class User
{
public User()
{
Roles = new List<Role>();
}
public string Id { get; set; }
public string Username { get; set; }
public virtual ICollection<Role> Roles { get; set; }
Below is definition of the Role entity
public class Role
{
public string Id { get; set; }
public string Name { get; set; }
public string Description { get; set; }
What i want is to define the many to many relationship and generate a relationship table UserRole which use UserId as the left key and RoleId as the right key, so how to write the configuration code?

Answer 1

User:
public class User
{
public User()
{
Roles = new List<Role>();
}
public string Id { get; set; }
public string Username { get; set; }
public virtual ICollection<UserRole> Roles { get; set; }
}
Role:
public class Role
{
public string Id { get; set; }
public string Name { get; set; }
public string Description { get; set; }
}
UserRole:
public class UserRole
{
public string Id { get; set; }
public string UserId { get; set; }
public string RoleId{ get; set; }
public virtual User User { get; set; }
public virtual Role Role { get; set; }
}
Override the OnModelCreating method in your dbcontext:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Entity<User>()
.HasMany(c => c.Roles )
.WithMany()
.Map(x =>
{
x.MapLeftKey("UserId");
x.MapRightKey("RoleId");
x.ToTable("UserRoles");
});
}