<span style="font-family:'宋体';font-size:10.5pt;"></span> 

private void CheckTopDomainName(HttpContext context) 
     { 
       Uri url = context.Request.Url; 
       string host = url.Host.ToLower(); 
  
       int count = host.Split('.').Length; 
       bool doubleDomainName = host.EndsWith(".com.cn", StringComparison.CurrentCultureIgnoreCase) || 
         host.EndsWith(".net.cn", StringComparison.CurrentCultureIgnoreCase) || 
         host.EndsWith(".gov.cn", StringComparison.CurrentCultureIgnoreCase) || 
         host.EndsWith(".org.cn", StringComparison.CurrentCultureIgnoreCase); 
  
       if (count == 2 || (count == 3 && doubleDomainName)) 
       { 
         context.Response.Status = "301 Moved Permanently"; 
         // 避免替换掉后面的参数中的域名 
         context.Response.AddHeader( 
           "Location",  
           url.AbsoluteUri.Replace( 
             string.Format("http://{0}", host),  
             string.Format("http://www.{0}", host) 
             ) 
           ); 
       } 

//判断是否是www.开头，如果不是301调整到www.域名 
if (!System.Web.HttpContext.Current.Request.Url.ToString().StartsWith("http://www.")) 
{ 
   //301 重定向到 /目录下           
   HttpContext.Current.Response.StatusCode = 301; 
   HttpContext.Current.Response.Status = "301 Moved Permanently"; 
   HttpContext.Current.Response.AddHeader("Location", "http://www.qinquan.org/"); 
   HttpContext.Current.Response.End(); 
}

if (!System.Web.HttpContext.Current.Request.RawUrl.EndsWith("/")) 
{ 
     //301 重定向到 /目录下 
     HttpContext.Current.Response.StatusCode = 301; 
     HttpContext.Current.Response.Status = "301 Moved Permanently"; 
     HttpContext.Current.Response.AddHeader("Location", System.Web.HttpContext.Current.Request.RawUrl + "/");        
     HttpContext.Current.Response.End(); 
}