与.net中的数据注释相反？

ASP.NET中[Compare(" ")]数据注释的反面/否定是什么？

即：两个属性必须包含不同的值。

 public string UserName { get; set; } [Something["UserName"]] public string Password { get; set; } 

Answer 1

您可以使用MVC Foolproof Validation中包含的[NotEqualTo]数据注释运算符。 我现在用它，效果很好！

MVC Foolproof是一个由@ nick-riggs创建的开源库，有很多可用的validation器。 除了进行服务器端validation之外，它还可以进行客户端不显眼的validation。

开箱即用的内置validation器的完整列表：

包含的运算符validation器

 [Is] [EqualTo] [NotEqualTo] [GreaterThan] [LessThan] [GreaterThanOrEqualTo] [LessThanOrEqualTo] 

包含必需的validation者

 [RequiredIf] [RequiredIfNot] [RequiredIfTrue] [RequiredIfFalse] [RequiredIfEmpty] [RequiredIfNotEmpty] [RequiredIfRegExMatch] [RequiredIfNotRegExMatch] 

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注意：如果您打算使用MVC Foolproof lib并支持本地化 ，请确保应用我在此提供的补丁 ： https ： //foolproof.codeplex.com/SourceControl/list/patches

Answer 2

这是@ Sverker84引用的链接的实现（服务器端）。

 [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)] public class UnlikeAttribute : ValidationAttribute { private const string DefaultErrorMessage = "The value of {0} cannot be the same as the value of the {1}."; public string OtherProperty { get; private set; } public UnlikeAttribute(string otherProperty) : base(DefaultErrorMessage) { if (string.IsNullOrEmpty(otherProperty)) { throw new ArgumentNullException("otherProperty"); } 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) { var otherProperty = validationContext.ObjectInstance.GetType() .GetProperty(OtherProperty); var otherPropertyValue = otherProperty .GetValue(validationContext.ObjectInstance, null); if (value.Equals(otherPropertyValue)) { return new ValidationResult( FormatErrorMessage(validationContext.DisplayName)); } } return ValidationResult.Success; } } 

用法：

 public string UserName { get; set; } [Unlike("UserName")] public string AlternateId { get; set; } 

有关此实现的详细信息以及如何在客户端实现它，请访问：

http://www.devtrends.co.uk/blog/the-complete-guide-to-validation-in-asp.net-mvc-3-part-2

http://www.macaalay.com/2014/02/25/unobtrusive-client-and-server-side-not-equal-to-validation-in-mvc-using-custom-data-annotations/

Answer 3

在get / set逻辑中使用它：

stringA.Equals（stringB）== false

Answer 4

除了@Eitan K提供的解决方案之外，如果您想使用其他属性的显示名称而不是其他属性的名称 ，请使用以下代码段：

 [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)] public class UnlikeAttribute : ValidationAttribute { private const string DefaultErrorMessage = "The value of {0} cannot be the same as the value of the {1}."; public string OtherPropertyDisplayName { get; private set; } public string OtherProperty { get; private set; } public UnlikeAttribute(string otherProperty) : base(DefaultErrorMessage) { if (string.IsNullOrEmpty(otherProperty)) { throw new ArgumentNullException("otherProperty"); } OtherProperty = otherProperty; } public override string FormatErrorMessage(string name) { return string.Format(ErrorMessageString, name, OtherPropertyDisplayName); } protected override ValidationResult IsValid(object value, ValidationContext validationContext) { if (value != null) { var otherProperty = validationContext.ObjectInstance.GetType() .GetProperty(OtherProperty); var otherPropertyValue = otherProperty .GetValue(validationContext.ObjectInstance, null); if (value.Equals(otherPropertyValue)) { OtherPropertyDisplayName = otherProperty.GetCustomAttribute().Name; return new ValidationResult( FormatErrorMessage(validationContext.DisplayName)); } } return ValidationResult.Success; } } 

Answer 5

服务器端和客户端validation的完整代码如下：

 [AttributeUsage(AttributeTargets.Property)] public class UnlikeAttribute : ValidationAttribute, IClientModelValidator { private string DependentProperty { get; } public UnlikeAttribute(string dependentProperty) { if (string.IsNullOrEmpty(dependentProperty)) { throw new ArgumentNullException(nameof(dependentProperty)); } DependentProperty = dependentProperty; } protected override ValidationResult IsValid(object value, ValidationContext validationContext) { if (value != null) { var otherProperty = validationContext.ObjectInstance.GetType().GetProperty(DependentProperty); var otherPropertyValue = otherProperty.GetValue(validationContext.ObjectInstance, null); if (value.Equals(otherPropertyValue)) { return new ValidationResult(ErrorMessage = ErrorMessage); } } return ValidationResult.Success; } public void AddValidation(ClientModelValidationContext context) { MergeAttribute(context.Attributes, "data-val", "true"); MergeAttribute(context.Attributes, "data-val-unlike", ErrorMessage); MergeAttribute(context.Attributes, "data-val-unlike-property", DependentProperty); } private void MergeAttribute(IDictionary attributes, string key, string value) { if (attributes.ContainsKey(key)) { return; } attributes.Add(key, value); } } 

然后在JavaScript中包含以下内容：

 $.validator.addMethod('unlike', function (value, element, params) { var propertyValue = $(params[0]).val(); var dependentPropertyValue = $(params[1]).val(); return propertyValue !== dependentPropertyValue; }); $.validator.unobtrusive.adapters.add('unlike', ['property'], function (options) { var element = $(options.form).find('#' + options.params['property'])[0]; options.rules['unlike'] = [element, options.element]; options.messages['unlike'] = options.message; }); 

用法如下：

  public int FromId { get; set; } [Unlike(nameof(FromId), ErrorMessage = "From ID and To ID cannot be the same")] public int ToId { get; set; }