asp.net-mvc – 嵌套对象的远程ViewModel验证无效

public class User
{
    public int UserId { get; set; }

    [Required(ErrorMessage = "A username is required.")]
    [StringLength(20,ErrorMessage = "Your username must be 4-20 characters.",MinimumLength = 4)]
    [RegularExpression("^[a-zA-Z0-9]*$",ErrorMessage = "Your username can only consist of letters and numbers.")]
    [Remote("UsernameExists","RemoteValidation",ErrorMessage = "Username is already taken")]
    public string Username { get; set; }

    [Required(ErrorMessage = "A password is required.")]
    [MinLength(4,ErrorMessage = "Your password must have at least 4 letters.")]
    public string Password { get; set; }

    [Required(ErrorMessage = "An email address is required.")]
    public string Email { get; set; }
}

对于Register功能,我创建了一个ViewModel,它包含一个User对象和一个用于密码确认的字符串：

public class RegistrationViewModel
{
    public User User { get; set; }

    [DisplayName("Password confirmation")]
    [Required,Compare("User.Password",ErrorMessage = "The password do not match")]
    public string PasswordConfirmation { get; set; }
}

我遇到的第一个问题是我似乎无法通过比较验证(“User.Password”),因为它似乎没有找到用户的属性.有没有办法根据User.Password属性验证PasswordConfirmation属性？

第二个问题是用户名字段的远程验证.我在http://davidhayden.com/blog/dave/archive/2011/01/04/ASPNETMVC3RemoteValidationTutorial.aspx跟随David Hayden的教程,但UsernameExists方法中的参数username始终为null.我在这里错过了什么吗？

编辑：

对不起,但我对于收到的密码比较错误实际上并不清楚.填写字段时工作正常,如果密码不匹配,我将收到错误.但是,在提交表单时,我在验证摘要中收到以下错误：找不到名为UserToRegister.Password的属性.

编辑2：

由于Joe的帖子,我已经找到了部分问题.远程验证器回发URL /？UserToRegister.Username = temp,这显然与我的控制器操作的username参数不匹配.为了将我的action参数映射到UserToRegister.Username,需要以下内容：

public ActionResult UsernameExists([Bind(Prefix = "UserToRegister.Username")]string username)

现在,这正确地将参数传递给方法.但是,在密码字段上使用Compare属性时仍然会出现错误.

谢谢.