Asp.net anti-leech

<% @ Webhandler Language = "C #" class = "handler" %>

Using system;
Using system. Web;

Public class handler: ihttphandler {
   
   Public void processrequest (httpcontext context ){
       If (context. Request. urlreferrer. Host = "10.11.43.52 ")
       {
           Context. response. expires = 0;
           Context. response. Clear ();
           Context. response. contenttype = "image/jpg ";
           Context. response. writefile (context. Request. physicalpath );
           Context. response. End ();
       }
       Else
       {
           Context. response. expires = 0;
           Context. response. Clear ();
           Context. response. contenttype = "image/jpg ";
           Context. response. writefile (context. Request. physicalapplicationpath + "error.jpg ");
           Context. response. End ();
       }
   }
 
   Public bool isreusable {
       Get {
           Return true;
       }
   }

}

1. The general processing program file (which can be directly compiled under vs2008). If it is vs2005, it must be written to app_code and then compiled.

Using system;
Using system. Data;
Using system. configuration;
Using system. Web;
Using system. Web. Security;
Using system. Web. UI;
Using system. Web. UI. webcontrols;
Using system. Web. UI. webcontrols. webparts;
Using system. Web. UI. htmlcontrols;

/// <Summary>
/// Handler Summary
/// </Summary>

 

Public class handler: ihttphandler {
   Public handler ()
   {
       //
       // Todo: add the constructor logic here
       //
   }
   
   Public void processrequest (httpcontext context ){
       If (context. Request. urlreferrer. Host = "10.11.43.52 ")
       {
           Context. response. expires = 0;
           Context. response. Clear ();
           Context. response. contenttype = "image/jpg ";
           Context. response. writefile (context. Request. physicalpath );
           Context. response. End ();
       }
       Else
       {
           Context. response. expires = 0;
           Context. response. Clear ();
           Context. response. contenttype = "image/jpg ";
           Context. response. writefile (context. Request. physicalapplicationpath + "error.jpg ");
           Context. response. End ();
       }
   }
 
   Public bool isreusable {
       Get {
           Return true;
       }
   }

}

2. Configure the Web. config file as follows: process and intercept handler content

<? XML version = "1.0"?>
<! --
   Note: In addition to manually editing this file, you can also use
   Web management tools to configure application settings. You can use
    "Website"-> "ASP. NET configuration" option.
   The complete list of settings and comments is displayed in
   In machine. config. Comments, this file is usually located in
   \ Windows \ Microsoft. NET \ framework \ v2.x \ config
-->
<Configuration>
 <Appsettings/>
 <Connectionstrings/>
 <System. Web>
  <! --
           Set compilation DEBUG = "true" to insert the debugging symbol
           Compiled pages. However, this
           Performance is affected, so this value is only available during development.
           Set to true.
       -->
  <Compilation DEBUG = "true"/>
  <! --
           In the <authentication> section, you can configure
           Security Authentication mode,
           To identify the user.
       -->
  <Authentication mode = "Windows"/>
  <! --
           If an unprocessed error occurs during request execution,
           You can configure the corresponding processing steps in the <mermerrors> section. Specifically,
           This section allows developers to configure
           HTML error page to be displayed
           To replace the error stack trace.

       <Customerrors mode = "remoteonly" defaultredirect = "genericerrorpage.htm">
           <Error statuscode = "403" Redirect = "noaccess.htm"/>
           <Error statuscode = "404" Redirect = "filenotfound.htm"/>
       </Customerrors>
  
       -->
  <Httphandlers>
   <Add verb = "*" Path = "*. jpg" type = "handler"/> 
  </Httphandlers>
 </System. Web>
</Configuration>

3rd, configure iisand filter the iiss' asp.netprocessing content, and specify the same dll as aspx for the .jpg file.

Page code:

<% @ Page Language = "C #"Codefile = "default. aspx. cs" inherits = "_ default" %>

<! 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> No title page </title>
</Head>
<Body>
   <Form ID = "form1" runat = "server">
   <Div>
        & nbsp; </div>
   </Form>
</Body>
</Html>