ASP.NET MVC中的验证
1.简单验证
在ASP.Net MVC中，验证是在Controller层，而错误呈现是在View层，Controller层是通过ModelState属性进行验证的,ModelState的状态是通过AddModelError()方法进行 添加的。
而在View层，是通过Html的辅助方法进行呈现的，这两个辅助方法分别是
- Html.ValidationMessage()
- Html.ValidationSummary()
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Create([Bind(Exclude = " CustomerId " )] Customer customer)
{
if (customer.CompanyName.Length == 0 )
{
ModelState.AddModelError( " CompanyName " , " CompanyName不能为空 " );
}
if (customer.EmailAddress.Length == 0 )
{
ModelState.AddModelError( " EmailAddress " , " EmailAddress不能为空 " );
}
if ( ! ModelState.IsValid)
{
return View();
}
try
{
_entities.AddToCustomer(customer);
_entities.SaveChanges();
return RedirectToAction( " Index " );
}
catch
{
return View();
}
}
<% @ Page Title = "" Language = " C# " MasterPageFile = " ~/Views/Shared/Site.Master " Inherits = " System.Web.Mvc.ViewPage<MvcApplication4.Models.Customer> " %>
< asp:Content ID ="Content1" ContentPlaceHolderID ="TitleContent" runat ="server" >
Create
</ asp:Content >
< asp:Content ID ="Content2" ContentPlaceHolderID ="MainContent" runat ="server" >
< h2 > Create </ h2 >
<% = Html.ValidationSummary( " Create was unsuccessful. Please correct the errors and try again. " ) %>
<% using (Html.BeginForm()) { %>
< fieldset >
< legend > Fields </ legend >
< p >
< label for ="NameStyle" > NameStyle: </ label >
<% = Html.TextBox( " NameStyle " ) %>
<% = Html.ValidationMessage( " NameStyle " , " * " ) %>
</ p >
< p >
< label for ="Title" > Title: </ label >
<% = Html.TextBox( " Title " ) %>
<% = Html.ValidationMessage( " Title " , " * " ) %>
</ p >
< p >
< label for ="FirstName" > FirstName: </ label >
<% = Html.TextBox( " FirstName " ) %>
<% = Html.ValidationMessage( " FirstName " , " * " ) %>
</ p >
< p >
< label for ="MiddleName" > MiddleName: </ label >
<% = Html.TextBox( " MiddleName " ) %>
<% = Html.ValidationMessage( " MiddleName " , " * " ) %>
</ p >
< p >
< label for ="LastName" > LastName: </ label >
<% = Html.TextBox( " LastName " ) %>
<% = Html.ValidationMessage( " LastName " , " * " ) %>
</ p >
< p >
< label for ="Suffix" > Suffix: </ label >
<% = Html.TextBox( " Suffix " ) %>
<% = Html.ValidationMessage( " Suffix " , " * " ) %>
</ p >
< p >
< label for ="CompanyName" > CompanyName: </ label >
<% = Html.TextBox( " CompanyName " ) %>
<% = Html.ValidationMessage( " CompanyName " , " CompanyName不能为空 " ) %>
</ p >
< p >
< label for ="SalesPerson" > SalesPerson: </ label >
<% = Html.TextBox( " SalesPerson " ) %>
<% = Html.ValidationMessage( " SalesPerson " , " * " ) %>
</ p >
< p >
< label for ="EmailAddress" > EmailAddress: </ label >
<% = Html.TextBox( " EmailAddress " ) %>
<% = Html.ValidationMessage( " EmailAddress " , " EmailAddress不能为空 " ) %>
</ p >
< p >
< label for ="Phone" > Phone: </ label >
<% = Html.TextBox( " Phone " ) %>
<% = Html.ValidationMessage( " Phone " , " * " ) %>
</ p >
< p >
< label for ="PasswordHash" > PasswordHash: </ label >
<% = Html.TextBox( " PasswordHash " ) %>
<% = Html.ValidationMessage( " PasswordHash " , " * " ) %>
</ p >
< p >
< label for ="PasswordSalt" > PasswordSalt: </ label >
<% = Html.TextBox( " PasswordSalt " ) %>
<% = Html.ValidationMessage( " PasswordSalt " , " * " ) %>
</ p >
< p >
< label for ="rowguid" > rowguid: </ label >
<% = Html.TextBox( " rowguid " ) %>
<% = Html.ValidationMessage( " rowguid " , " * " ) %>
</ p >
< p >
< label for ="ModifiedDate" > ModifiedDate: </ label >
<% = Html.TextBox( " ModifiedDate " ) %>
<% = Html.ValidationMessage( " ModifiedDate " , " * " ) %>
</ p >
< p >
< input type ="submit" value ="Create" />
</ p >
</ fieldset >
<% } %>
< div >
<% = Html.ActionLink( " Back to List " , " Index " ) %>
</ div >
</ asp:Content >
如果使用Entityframework生成的Model，数据库设计时为不为空，那么生成的Model层该字段的Nullable属性就为false，即使在Controller没有做简单验证，在View层也会做是否为空的判断的。
2.使用IDataErrorInfo Interface
IDataErrorInfo接口的定义比较简单：
public interface IDataErrorInfo
{
string this[string columnName] { get; }
string Error { get; }
}
使用IDataErrorInfo Interface的步骤如下：
- 针对Model，创建一个Partial类
- 添加OnChanging和OnChanged Partial方法
- 实现IDataErrorInfo接口
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel;
namespace MvcApplication4.Models
{
public partial class Customer:IDataErrorInfo
{
private Dictionary < string , string > _errors = new Dictionary < string , string > ();
partial void OnCompanyNameChanging(string value)
{
if (value.Trim().Length == 0)
{
_errors.Add("CompanyName", "CompanyName is required");
}
}
public string Error
{
get
{
return string.Empty;
}
}
public string this[string columnName]
{
get
{
if (_errors.ContainsKey(columnName))
{
return _errors[columnName];
}
return string.Empty;
}
}
}
}
3.使用Data Annotation Validators
- 下载Data Annotations Model Binder sample ，下载地址在http://aspnet.codeplex.com/Release/ProjectReleases.aspx?ReleaseId=24471
- 添加对 Microsoft.Web.Mvc.DataAnnotations.dll和System.ComponentModel.DataAnnotations.dll 的引用
- 在Global.asax.cs中的Application_Start()方法中配置
- 使用Data Annotation Validator Attributes
System.ComponentModel.DataAnnotations命名空间下包括四个属性： - Range:范围验证
- ReqularExpression：正则表达式验证
- Required：必须验证
- StringLength：字符串长度验证
- Validation：这是所有验证属性的基类。
using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
namespace MvcApplication4.Models
{
public class Test
{
public int Id { get ; set ; }
[Required]
[StringLength( 10 )]
public string Name { get ; set ; }
[Required]
public string Description { get ; set ; }
[DisplayName( " Price " )]
[Required]
[RegularExpression( @" ^/$?/d+(/.(/d{2}))?$ " )]
public decimal UnitPrice { get ; set ; }
}
}