asp.net mvc filter

Using Filters to Attach Reusable Behaviors

 

Introducing the Four Basic Types of Filters

 

 

Notice that ActionFilterAttribute is the default implementation for both IActionFilter
and IResultFilter—it implements both of those interfaces. It’s meant to be totally general
purpose, so it doesn’t provide any implementation (in fact, it’s marked abstract, so you can
only use it by deriving a subclass from it). However, the other default implementations
(AuthorizeAttribute and HandleErrorAttribute) are concrete, contain useful logic, and can
be used without deriving a subclass.
To get a better understanding of these types and their relationships, examine Figure 9-6.
It shows that all filter attributes are derived from FilterAttribute, and also implement one or
more of the filter interfaces. The dark boxes represent ready-to-use concrete filters; the rest are
interfaces or abstract base classes. Later in this chapter, you’ll learn more about each built-in
filter type.

 

MyFilter Demo:

 

01using System;
02using System.Collections.Generic;
03using System.Linq;
04using System.Web;
05using System.Web.Mvc;
06 
07namespace TestMvcWebApp1.ActionResultEx
08{
09    public class ShowMessageAttribute:ActionFilterAttribute
10    {
11        public string Message { get; set; }
12        public override void OnActionExecuting(ActionExecutingContext filterContext)
13        {
14            filterContext.HttpContext.Response.Write("[BeforeAction " + Message + "]");
15        }
16        public override void OnActionExecuted(ActionExecutedContext filterContext)
17        {
18            filterContext.HttpContext.Response.Write("[AfterAction " + Message + "]");
19        }
20        public override void OnResultExecuting(ResultExecutingContext filterContext)
21        {
22            filterContext.HttpContext.Response.Write("[BeforeResult " + Message + "]");
23        }
24        public override void OnResultExecuted(ResultExecutedContext filterContext)
25        {
26            filterContext.HttpContext.Response.Write("[AfterResult " + Message + "]");
27        }
28    }
29}

 

 

 

使用：

 

01using System;
02using System.Collections.Generic;
03using System.Linq;
04using System.Web;
05using System.Web.Mvc;
06using TestMvcWebApp1.ActionResultEx;
07using System.Data.SqlClient;
08 
09namespace TestMvcWebApp1.Controllers
10{
11    public class ShowMessageDemoController : Controller
12    {
13        //
14        // GET: /ShowMessageDemo/
15        [ShowMessage(Message = "这是我的信息A" , Order=1)]
16        [HandleError(View="Problem")]
17        public ActionResult Index()
18        {
19            int a = 0;
20            SqlConnection conn = new SqlConnection();
21            conn.Open();
22 
23            return Content("  网页内容  ");
24        }
25 
26    }
27}

 

输出结果：

[BeforeAction 这是我的信息A][AfterAction 这是我的信息A]

[BeforeResult 这是我的信息A]  网页内容  [AfterResult 这是我的信息A]

 

 <customErrors mode="On"></customErrors>

 

posted @ 2011-10-09 17:12  PointNet  阅读(256)  评论(0)  编辑  收藏  举报