在asp.net核心中使用连接查询获取实体框架中的用户角色

public class ApplicationDbContext : DbContext
{
    public DbSet<User> Users { get; set; }
    public DbSet<Role> Roles { get; set; }
    public DbSet<UserRole> UserRoles { get; set; }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<UserRole>()
            .HasKey(ur => new { ur.UserId, ur.RoleId });

        modelBuilder.Entity<UserRole>()
            .HasOne(ur => ur.User)
            .WithMany(u => u.UserRoles)
            .HasForeignKey(ur => ur.UserId);

        modelBuilder.Entity<UserRole>()
            .HasOne(ur => ur.Role)
            .WithMany(r => r.UserRoles)
            .HasForeignKey(ur => ur.RoleId);
    }
}

public class UserController : Controller
{
    private readonly ApplicationDbContext _context;

    public UserController(ApplicationDbContext context)
    {
        _context = context;
    }

    public IActionResult GetUserRoles(int userId)
    {
        var userRoles = _context.UserRoles
            .Where(ur => ur.UserId == userId)
            .Include(ur => ur.Role)
            .Select(ur => ur.Role)
            .ToList();

        return View(userRoles);
    }
}