MVC3验证检查，如果属性值不同

Question

在MVC3您可以添加验证模型，以检查是否属性匹配，就像这样：

public string NewPassword { get; set; } 

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

有没有一种方法来检查两个属性在下面做，相信喜欢不同码？

[CheckPropertiesDiffer("OldPassword", 
ErrorMessage = "Old and new passwords cannot be the same")] 
public string OldPassword { get; set; } 

public string ConfirmPassword { get; set; } 

Answer 1

这里是你可以在模型中使用什么：

public string OldPassword 

[NotEqualTo("OldPassword", ErrorMessage = "Old and new passwords cannot be the same.")] 
public string NewPassword { get; set; } 

然后定义如下荷兰国际集团自定义属性：

public class NotEqualToAttribute : ValidationAttribute 
{ 
    private const string defaultErrorMessage = "{0} cannot be the same as {1}."; 

    private string otherProperty; 

    public NotEqualToAttribute(string otherProperty) : base(defaultErrorMessage) 
    { 
     if (string.IsNullOrEmpty(otherProperty)) 
     { 
      throw new ArgumentNullException("otherProperty"); 
     } 

     this.otherProperty = otherProperty; 
    } 

    public override string FormatErrorMessage(string name) 
    { 
     return string.Format(ErrorMessageString, name, otherProperty); 
    } 

    protected override ValidationResult IsValid(object value, ValidationContext validationContext) 
    { 
     if (value != null) 
     { 
      PropertyInfo otherPropertyInfo = validationContext.ObjectInstance.GetType().GetProperty(otherProperty); 

      if (otherPropertyInfo == null) 
      { 
       return new ValidationResult(string.Format("Property '{0}' is undefined.", otherProperty)); 
      } 

      var otherPropertyValue = otherPropertyInfo.GetValue(validationContext.ObjectInstance, null); 

      if (otherPropertyValue != null && !string.IsNullOrEmpty(otherPropertyValue.ToString())) 
      { 
       if (value.Equals(otherPropertyValue)) 
       { 
        return new ValidationResult(this.FormatErrorMessage(validationContext.DisplayName)); 
       } 
      } 
     } 

     return ValidationResult.Success; 
    }   
} 

Answer 2

我不认为已经有一个内置的属性提供这种功能。 最好的办法是创建您自己的自定义属性，如在那里详细描述： http://www.codeproject.com/KB/aspnet/CustomValidation.aspx

Answer 3

我会检查控制器。

在控制器：

if(model.ConfirmPassword == model.OldPassword){ 
    ModelState.AddModelError("ConfirmPassword", "Old and new passwords cannot be the same"); 
} 

在View：

@Html.ValidationMessage("ConfirmPassword") 

希望这有助于

Answer 4

你也可以实现一流水平的验证就像这里的描述：http://weblogs.asp.net/scottgu/archive/2010/12/10/class-level-model-validation-with-ef-code-first-and-asp-net-mvc-3.aspx

基本上你实现IValidatableObject的验证方法，并且可以访问任何你想要的属性。

public class MyClass : IValidateableObject 
{ 
    public string NewPassword { get; set; } 
    public string OldPassword { get; set; } 

    public IEnumerable<ValidationResult> Validate(ValidationContext context) 
    { 
     if (NewPassword == OldPassword) 
      yield return new ValidationResult("Passwords should not be the same"); 
    } 
}