图片防盗链asp.net 实现

 1  public class UrlHandler : IHttpHandler
 2     {
 3         //指明该HttpHandler的实现类是否需要缓存
 4         public bool IsReusable
 5         {
 6             get { return true; }
 7         }
 8         public UrlHandler()
 9         {
10         }
11         public void ProcessRequest(HttpContext context)
12         {
13             string FileName = context.Server.MapPath(context.Request.FilePath);
14             if (context.Request.UrlReferrer == null)
15             {
16                 context.Response.ContentType = "image/JPEG";
17                 context.Response.WriteFile("~/no.jpg");//被替换图片
18             }
19             else
20             {
21                 if (context.Request.UrlReferrer.Host.IndexOf("localhost") > -1)//这里是你的域名,如www.maticsoft.com
22                 {
23                     context.Response.ContentType = "image/JPEG";
24                     context.Response.WriteFile(FileName);
25                 }
26                 else
27                 {
28                     context.Response.ContentType = "image/JPEG";
29                     context.Response.WriteFile("~/no.jpg");
30                 }
31             }
32         }        
33     }