找不到类型或名称空间Compare（您是否缺少using指令或程序集引用？）

我正在尝试向网站添加管理员。在我的AccountsModels.cs上发现了问题

它只需要比较实现的数据，但我似乎会收到此错误。

我也有一个观点：
-Register.cshtml
-LogOn.cshtml
-ChangePasswordSuccess.cshtml
-ChangePassword.cshtml

＆当然是AccountController.cs。

有人知道解决方案吗？

这是代码：

using System.ComponentModel.DataAnnotations;
using System.Web.Mvc;
using System.Web.Security;

namespace Videoteek.Domain.Models
{
    public class ChangePasswordModel
    {
        [Required]
        [DataType(DataType.Password)]
        [Display(Name = "Current password")]
        public string OldPassword { get; set; }

        [Required]
        [StringLength(100, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 6)]
        [DataType(DataType.Password)]
        [Display(Name = "New password")]
        public string NewPassword { get; set; }

        [DataType(DataType.Password)]
        [Display(Name = "Confirm new password")]
        [Compare("NewPassword", ErrorMessage = "The new password and confirmation password do not match.")]
        public string ConfirmPassword { get; set; }
    }

    public class LogOnModel
    {
        [Required]
        [Display(Name = "User name")]
        public string UserName { get; set; }

        [Required]
        [DataType(DataType.Password)]
        [Display(Name = "Password")]
        public string Password { get; set; }

        [Display(Name = "Remember me?")]
        public bool RememberMe { get; set; }
    }

    public class RegisterModel
    {
        [Required]
        [Display(Name = "User name")]
        public string UserName { get; set; }

        [Required]
        [DataType(DataType.EmailAddress)]
        [Display(Name = "Email address")]
        public string Email { get; set; }

        [Required]
        [StringLength(100, ErrorMessage = "The {0} must be at least {2} characters long.", MinimumLength = 6)]
        [DataType(DataType.Password)]
        [Display(Name = "Password")]
        public string Password { get; set; }

        [DataType(DataType.Password)]
        [Display(Name = "Confirm password")]
        [Compare("Password", ErrorMessage = "The password and confirmation password do not match.")]
        public string ConfirmPassword { get; set; }

        //****
        [Required]
        [Display(Name = "Security Question")]
        public string PwdQuestion { get; set; }
        [Required]
        [Display(Name = "Security Answer")]
        public string PwdAnswer { get; set; }

    }
}