之前写过一篇文章《ASP.NET MVC中的验证》,唯一的遗憾就是在使用Data Annotation Validators方式验证的时候,如果数据库是Entityframework等自动生成的文件,就没有办法使用扩展属性标记进行标记。现在已经开始有了一些其它的Asp.net MVC 验证框架,使用上跟Data Annotation Validators差不太多,但是普遍有这样的问题,如果数据库是Entityframework生成的edm文件,没有办法进行扩展属性标记。
今天在网上发现了另外一个 Asp.net MVC 验证框架---xVal框架,使用上跟Data Annotation Validators非常接近,也有类似的问题。
简单介绍下,xVal是一个开源的asp.net mvc验证框架,有关它的介绍,可以参考:《xVal - a validation framework for ASP.NET MVC》
xVal使用了MS-PL的开源协议 ,也就是说,它允许用户看、修改和分发源代码,而不论出自商业用途还是非商业用途,类似BSD许可证。
xVal可以通过IRulesProvider接口,通过这个接口可以进行扩展,很明显,它只扩展了Castle框架跟NHibernate框架,通过如下两个程序集就可以看出来:
- xVal.RulesProviders.CastleValidator.dll
- xVal.RulesProviders.NHibernateValidator.dll
最终,网上的一片文章给了我提示,问题得到了解决,解决的思路就是建立一个伙伴类,这个伙伴类跟原来的类的结构定义是一样的,在进行验证的时候,不对edm文件中的类进行验证,而是对伙伴类进行验证。
这里就以xVal框架为例进行Demo演示吧。
首先我们建立一个类模拟Entityframework生成的edm文件中的类,类的定义代码如下:
{
public string UserName { get ; set ; }
public string Password { get ; set ; }
public string Address { get ; set ; }
public string Telephone { get ; set ; }
public int Age { get ; set ; }
public string Email { get ; set ;}
}
接下来我们建立一个伙伴类
{
[Required]
[StringLength( 10 )]
public string UserName { get ; set ; }
[Required]
[StringLength( 18 )]
[DataType(DataType.Password)]
public string Password { get ; set ; }
[Required]
[StringLength( 100 )]
public string Address { get ; set ; }
[Required]
[DataType(DataType.PhoneNumber)]
public string Telephone { get ; set ; }
[Required]
[Range( 1 , 100 )]
public int Age { get ; set ; }
[Required]
[DataType(DataType.EmailAddress)]
public string Email { get ; set ; }
}
再接下来,我们使用partial关键字为User类进行扩展,扩展类的定义如下:
public partial class User
{
}
注意这段代码:[MetadataType(typeof(UserMetadata))]
为了方便大家阅读,我把整体代码贴出来,整体代码如下:
namespace MVCValidate.Models
{
public partial class User
{
public string UserName { get ; set ; }
public string Password { get ; set ; }
public string Address { get ; set ; }
public string Telephone { get ; set ; }
public int Age { get ; set ; }
public string Email { get ; set ;}
}
[MetadataType( typeof (UserMetadata))]
public partial class User
{
}
public class UserMetadata
{
[Required]
[StringLength( 10 )]
public string UserName { get ; set ; }
[Required]
[StringLength( 18 )]
[DataType(DataType.Password)]
public string Password { get ; set ; }
[Required]
[StringLength( 100 )]
public string Address { get ; set ; }
[Required]
[DataType(DataType.PhoneNumber)]
public string Telephone { get ; set ; }
[Required]
[Range( 1 , 100 )]
public int Age { get ; set ; }
[Required]
[DataType(DataType.EmailAddress)]
public string Email { get ; set ; }
}
}
接下来,我们要实现伙伴类跟原类的替换方法了,代码如下所示:
using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using xVal.ServerSide;
namespace MVCValidate.Models
{
internal static class DataAnnotationsValidationRunner
{
// TODO: DOES NOT SUPPORT METADATA TYPE
/// // Warning: For some reason, DataTypeAttribute.IsValid() always returns "true", regardless of whether
/// // it is actually valid. Need to improve this test runner to fix that.
// public static IEnumerable<ErrorInfo> GetErrors(object instance)
// {
// return from prop in TypeDescriptor.GetProperties(instance).Cast<PropertyDescriptor>()
// from attribute in prop.Attributes.OfType<ValidationAttribute>()
// where !attribute.IsValid(prop.GetValue(instance))
// select new ErrorInfo(prop.Name, attribute.FormatErrorMessage(string.Empty), instance);
// }
/// <summary>
/// Get any errors associated with the model also investigating any rules dictated by attached Metadata buddy classes.
/// </summary>
/// <param name="instance"></param>
/// <returns></returns>
public static IEnumerable < ErrorInfo > GetErrors( object instance)
{
var metadataAttrib = instance.GetType().GetCustomAttributes( typeof (MetadataTypeAttribute), true ).OfType < MetadataTypeAttribute > ().FirstOrDefault();
var buddyClassOrModelClass = metadataAttrib != null ? metadataAttrib.MetadataClassType : instance.GetType();
var buddyClassProperties = TypeDescriptor.GetProperties(buddyClassOrModelClass).Cast < PropertyDescriptor > ();
var modelClassProperties = TypeDescriptor.GetProperties(instance.GetType()).Cast < PropertyDescriptor > ();
return from buddyProp in buddyClassProperties
join modelProp in modelClassProperties on buddyProp.Name equals modelProp.Name
from attribute in buddyProp.Attributes.OfType < ValidationAttribute > ()
where ! attribute.IsValid(modelProp.GetValue(instance))
select new ErrorInfo(buddyProp.Name, attribute.FormatErrorMessage( string .Empty), instance);
}
}
}
完成以上的代码以后,大部分工作就完成了,接下来,我们在Controller中编写一个create方法,来模拟Create操作,代码如下所示:
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Mvc.Ajax;
using MVCValidate.Models;
using xVal.ServerSide;
namespace MVCValidate.Controllers
{
public class UserController : Controller
{
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Create(User user)
{
var errors = DataAnnotationsValidationRunner.GetErrors(user);
if (errors.Any())
{
new RulesException(errors).AddModelStateErrors(ModelState, " user " );
}
return View();
}
}
}
接下来,编写View层的代码,比较简单,我就直接贴出来了,代码如下:
<! DOCTYPE html PUBLIC " -//W3C//DTD XHTML 1.0 Transitional//EN " " http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd " >
< html xmlns = " http://www.w3.org/1999/xhtml " >
< head runat = " server " >
< title > Create </ title >
</ head >
< body >
<%= Html.ValidationSummary( " Create was unsuccessful. Please correct the errors and try again. " ) %>
<% using (Html.BeginForm()) { %>
< fieldset >
< legend > Fields </ legend >
< p >
< label for = " UserName " > UserName: </ label >
<%= Html.TextBox( " user.UserName " ) %>
<%= Html.ValidationMessage( " user.UserName " ) %>
</ p >
< p >
< label for = " Password " > Password: </ label >
<%= Html.TextBox( " user.Password " ) %>
<%= Html.ValidationMessage( " user.Password " ) %>
</ p >
< p >
< label for = " Address " > Address: </ label >
<%= Html.TextBox( " user.Address " ) %>
<%= Html.ValidationMessage( " user.Address " ) %>
</ p >
< p >
< label for = " Telephone " > Telephone: </ label >
<%= Html.TextBox( " user.Telephone " ) %>
<%= Html.ValidationMessage( " user.Telephone " ) %>
</ p >
< p >
< label for = " Age " > Age: </ label >
<%= Html.TextBox( " user.Age " ) %>
<%= Html.ValidationMessage( " user.Age " ) %>
</ p >
< p >
< label for = " Email " > Email: </ label >
<%= Html.TextBox( " user.Email " ) %>
<%= Html.ValidationMessage( " user.Email " ) %>
</ p >
< p >
< input type = " submit " value = " Create " />
</ p >
</ fieldset >
<% } %>
< div >
<%= Html.ActionLink( " Back to List " , " Index " ) %>
</ div >
</ body >
</ html >
最终的效果如下图所示:
Asp.net mvc开源验证框架非常的多,只是有相似问题的更多,有了这个通用的方法,就可以很容易对其他验证框架进行扩展了。
最后,为了方便大家学习,代码我进行了打包,下载地址在这里: