图片防盗链

新建一个类库AvoidImage 继承IHttpHandler，记得引用System.Web

 

class  AvoidImage : IHttpHandler
    {

         #region  IHttpHandler 成员

         public   bool  IsReusable
        {
             // get { throw new NotImplementedException(); }
             get  {
                 return   true ;
            }
        }

         #endregion
         public   void  ProcessRequest(HttpContext context)
        {
            Uri urlreferrer  =  context.Request.UrlReferrer; // 访问来源地址
             string  ip  =  context.Request.UserHostAddress; // 访问来源Ip地址
             string  serverhost  =  context.Request.Url.Host; // 当前访问主机地址
             string  localIp  =  ConfigurationManager.AppSettings[ " LocalIP " ];
             if  (urlreferrer  ==   null   ||  urlreferrer.Host.ToLower()  !=  serverhost.ToLower()  ||  ip  !=  localIp)
            {
                context.Response.WriteFile( " ~/images/index_adr11.gif " );
            }
             else
            {
                context.Response.WriteFile(context.Request.PhysicalPath);
            }
        }
    }

 

 

default.aspx

 

< body >
     < form  id ="form1"  runat ="server" >
     < div >
     < img  src ="images/Advertise_1.jpg"   />
     div >
     form >
body >