两个属性asp.net mvc之间的条件的数据验证属性

Question

我想在两个属性之间放置一个规则,即一个属性必须大于另一个属性.那么什么是数据验证属性可以让我这样做？

这是我的财产

  public int Min{get;set;}
  public int Max{get;set;} 

你可以很容易地理解Max必须大于Min.

谢谢您的帮助!

Answer 1

对象的数据验证让我感到高兴(以及使用客户端验证).

这是一个可用于执行所要求的属性(可以比较实现IComparable的类型对)

public class GreaterThanAttribute : ValidationAttribute
{

    public GreaterThanAttribute(string otherProperty)
        : base("{0} must be greater than {1}")
    {
        OtherProperty = otherProperty;
    }

    public string OtherProperty { get; set; }

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

    protected override ValidationResult
        IsValid(object firstValue, ValidationContext validationContext)
    {
        var firstComparable = firstValue as IComparable;
        var secondComparable = GetSecondComparable(validationContext);

        if (firstComparable != null && secondComparable != null)
        {
            if (firstComparable.CompareTo(secondComparable) < 1)
            {
                object obj = validationContext.ObjectInstance;
                var thing = obj.GetType().GetProperty(OtherProperty);
                var displayName = (DisplayAttribute)Attribute.GetCustomAttribute(thing, typeof(DisplayAttribute));

                return new ValidationResult(
                    FormatErrorMessage(validationContext.DisplayName, displayName.GetName()));
            }
        }

        return ValidationResult.Success;
    }

    protected IComparable GetSecondComparable(
        ValidationContext validationContext)
    {
        var propertyInfo = validationContext
                              .ObjectType
                              .GetProperty(OtherProperty);
        if (propertyInfo != null)
        {
            var secondValue = propertyInfo.GetValue(
                validationContext.ObjectInstance, null);
            return secondValue as IComparable;
        }
        return null;
    }
}

然后你可以装饰你的模型:

  public int Min{get;set;}

  [GreaterThan("Min")]
  public int Max{get;set;}

这是一个有用的问题,关于低于验证MVC自定义验证:比较两个日期但适用于日期而不是整数但适用相同的方法

Answer 2

您可以使用Attribute或视图模型可以实现IValidatableObject。很好的是，asp.net mvc modelbinder将在发布后自动运行它。

public class TestCompareModel : IValidatableObject
{
    [Required]
    public Int32 Low { get; set; }

    [Required]
    public Int32 High { get; set; }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        var results = new List<ValidationResult>();

        if (High < Low)
            results.Add(new ValidationResult("High cannot be less than low"));

        return results;
    }
}

控制器动作：

    [HttpPost]
    public ActionResult Test(TestCompareModel viewModel)
    {
        if (!ModelState.IsValid)
            return View(viewModel);

        return RedirectToAction("Index");
    }

视图

@model Scratch.Web.Models.TestCompareModel

@{
    ViewBag.Title = "Test";
}

<h2>Test</h2>

@using (Html.BeginForm()) 
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>TestCompareModel</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })
        <div class="form-group">
            @Html.LabelFor(model => model.Low, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.Low, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.Low, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.High, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.High, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.High, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
        </div>
    </div>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

Answer 3

您需要的功能可以使用 Jquery 轻松实现，如下所示：-

HTML :-

<input type="text" id="Max" name="Max"  />  //with model validations just make sure user can input numbers in Max and Min textboxes.
<input type="text" id="Min" name="Min" />
<div id="errormess"></div>

jQuery：

$(document).ready(function(){
   $("#Max").focusout(function(){
      if(parseInt($(this).val()) < parseInt($("#Min").val()))
      {
         $("#errormess").html('Max value cannot be lower then Min Value');
      }
      else{ $("#errormess").html(''); }
   });

   $("#Min").focusout(function(){
      if(parseInt($(this).val()) > parseInt($("#Max").val()))
      {
         $("#errormess").html('Max value cannot be lower then Min Value');
      }
      else{ $("#errormess").html(''); }
   });
});

演示版