如何在 MVC 4 应用程序中创建替代必填字段?

How do I make an alternative required field in MVC 4 application?

我有一个 Model,在 MVC 4 中有 phone 号码和电子邮件。这有点像注册。因此用户可以提供电子邮件或手机号码phone 或两者。但是我不能为他们做一个替代的必填字段。 我的模型就像

public class RegisterModel
    {
        [Required]
        [Display(Name = "User name")]        
        [UsernameValidator(ErrorMessage = "Only Letters and numbers")]
        [System.Web.Mvc.Remote("IsUserExitst", "Account", HttpMethod = "POST", ErrorMessage = "This user name already exists. Try a new one.")]
        public string UserName { 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")]
        [System.ComponentModel.DataAnnotations.Compare("Password", ErrorMessage = "The password and confirmation password do not match.")]
        public string ConfirmPassword { get; set; }

        [Required]
        [MaxLength(50)]
        [EmailOrPhoneValidator(ErrorMessage = "Invalid Phone number")]
        [Display(Name = "Phone number")]
        [System.Web.Mvc.Remote("IsMobOrEmailExists", "Account", HttpMethod = "POST", ErrorMessage = "This Phone number or Email already exists. Try a new one.")]
        public string MobileNo { get; set; }


        [Required]
        [MaxLength(50)]
        [EmailAddress(ErrorMessage = "Invalid Email address")]
        [Display(Name = "Email")]
        [System.Web.Mvc.Remote("IsEmailExists", "Account", HttpMethod = "POST", ErrorMessage = "This Email already exists. Try a new one.")]
        public string Email { get; set; }
    }

这里我想交替使用EmailPhoneNo。我想写一个 class 作为自定义必填字段。我已经完成了这个问题,

  1. Question这里的答案提供了结合javascript的解决方案。但我不会用它。我将写下 class 文件并在此处实现我的逻辑。
  2. RequiredIf 似乎是我的问题的确切建议,但我很厌倦尝试该解决方案。我无法理解如何在我的项目中导入 .dll。它是在 Mvc 3
  3. 中开发的
  4. 另一个 solution,但这里他们在 class 中组合了替代属性。那么我该怎么做,因为我的属性是完全独立的。那么该怎么办。

我会选择解决方案 2 并创建一个 RequiredIf 验证属性。无需导入任何 DLL,因为您可以自己创建 class。下面是该属性的示例。它来自我在自己的代码中使用的 RequiredIfTrue 属性,我交换了验证逻辑以查找空值

public class RequiredIfEmpty : ValidationAttribute
{
    private string _fieldName;

    public RequiredIfEmpty(string fieldName)
    {
        _fieldName = fieldName;
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        var property = validationContext.ObjectType.GetProperty(_fieldName);
        if (property == null)
        {
            throw new ArgumentException("No property with the name " + _fieldName + " found.");
        }

        string fieldValue = (string)property.GetValue(validationContext.ObjectInstance, null);
        if (String.IsNullOrWhiteSpace(fieldValue))
        {
            return (value != null && !String.IsNullOrWhiteSpace((string)value) ? ValidationResult.Success : new ValidationResult(ErrorMessage));
        }
        else
        {
            return ValidationResult.Success;
        }
    }
}

在您的 ViewModel 中,您可以像使用任何其他属性一样使用该属性,但您必须指定替代项的名称 属性

[RequiredIfEmpty("Email", ErrorMessage = "Phone number invalid")]
[MaxLength(50)]
[Display(Name = "Phone number")]
[System.Web.Mvc.Remote("IsMobOrEmailExists", "Account", HttpMethod = "POST", ErrorMessage = "This Phone number or Email already exists. Try a new one.")]
public string MobileNo { get; set; }