我创建了一个从 ValidationAttribute 派生的自定义验证器。我的理解是它将为客户端脚本生成足够的元数据以自动验证（使用 jquery.validate）。自定义验证器在服务器端工作正常。但它不会在客户端触发错误消息。（其他默认验证器，如“StringLength”在客户端也可以正常工作。）我们如何纠正它？
public class Person
{
[Required(ErrorMessage = "First name required")]
public string FirstName { get; set; }
[CustomStartLetterMatch("FirstName")]
[StringLength(5,ErrorMessage = "Must be under 5 characters")]
public string LastName { get; set; }
[Range(18,50,ErrorMessage="Must be between 18 and 50")]
public int Age { get; set; }
}
public sealed class CustomStartLetterMatch : ValidationAttribute
{
private const string _defaultErrorMessage = " First letter of '{0}' must be same as first letetr of '{1}'";
private string _basePropertyName;
public CustomStartLetterMatch(string basePropertyName)
: base(_defaultErrorMessage)
{
_basePropertyName = basePropertyName;
}
//Override FormatErrorMessage Method
public override string FormatErrorMessage(string name)
{
return string.Format(_defaultErrorMessage, name, _basePropertyName);
}
//Override IsValid
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
//Get PropertyInfo Object
var basePropertyInfo = validationContext.ObjectType.GetProperty(_basePropertyName);
var baseValue = (string)basePropertyInfo.GetValue(validationContext.ObjectInstance, null);
var currentValue = (string)value;
string firstLetterBaseValue = baseValue.Substring(0, 1);
string firstLetterCurrentValue = currentValue.Substring(0, 1);
//Comparision
if (!string.Equals(firstLetterBaseValue, firstLetterCurrentValue))
{
var message = FormatErrorMessage(validationContext.DisplayName);
return new ValidationResult(message);
}
//Default return - This means there were no validation error
return null;
}
}
看法
@model MyValidationTEST.Person
<script src="@Url.Content("~/Scripts/jquery-1.5.1.min.js")" type="text/javascript"> </script>
@*UnObtrusive*@
<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>
@using (Html.BeginForm()) {
@Html.ValidationSummary(true)
<fieldset>
<legend>Person</legend>
<div class="editor-label">
@Html.LabelFor(model => model.FirstName)
</div>
<div class="editor-field">
@Html.EditorFor(model => model.FirstName)
@Html.ValidationMessageFor(model => model.FirstName)
</div>
<div class="editor-label">
@Html.LabelFor(model => model.LastName)
</div>
<div class="editor-field">
@Html.EditorFor(model => model.LastName)
@Html.ValidationMessageFor(model => model.LastName)
</div>
<div class="editor-label">
@Html.LabelFor(model => model.Age)
</div>
<div class="editor-field">
@Html.EditorFor(model => model.Age)
@Html.ValidationMessageFor(model => model.Age)
</div>
<p>
<input type="submit" value="Create" />
</p>
</fieldset>
}
<div>
@Html.ActionLink("Back to List", "Index")
</div>
阅读：