学步园

if(Request.ServerVariables["HTTP_REFERER"]!=null)
   {
    string HTTP_REFERER=Request.ServerVariables["HTTP_REFERER"].ToString().ToLower();
    string HTTP_HOST=Request.ServerVariables["HTTP_HOST"].ToString().ToLower();

    if(HTTP_HOST==HTTP_REFERER.Substring(7,HTTP_HOST.Length))
    {
     Response.Write("OK");
    }
    else
    {
     Response.Write("ERR");
    }
   }
   else
   {
    Response.Write("ERR");
   }