c# - The non-generic method cannot be used with type arguments in this context 是什么意思？

Question

我有以下类和方法:

public class UserManager<TUser, TKey> : IDisposable
    where TUser : class, global::Microsoft.AspNet.Identity.IUser<TKey>
    where TKey : global::System.IEquatable<TKey> {

   public virtual Task<TUser> FindByIdAsync(TKey userId);

和:

private ApplicationUserManager _userManager;
    public ApplicationUserManager UserManager
    {
        get
        {
            return _userManager ?? Request.GetOwinContext().GetUserManager<ApplicationUserManager>();
        }
        set
        {
            _userManager = value;
        }
    }

public class ApplicationUserManager : UserManager<ApplicationUser, int>
public class ApplicationUser : IdentityUser<int, CustomUserLogin, CustomUserRole, CustomUserClaim>

我想像这样调用这个方法:

var user = await UserManager.FindByIdAsync<ApplicationUser,int>(99);

它给我错误:

非泛型方法

'Microsoft.AspNet.Identity.UserManager.FindByIdAsync(int)' cannot be used with type arguments

Answer 1

如错误所述，FindByIdAsync不接受类型参数。这些存在于声明类 UserManager<TUser, TKey>

var user = await UserManager.FindByIdAsync(99);