http://blog.csdn.net/octverve/archive/2007/09/25/1800400.aspx
private int GetUrlError(string curl)
{
int num = 200;
if (this.method == 1)
{
HttpWebRequest request = (HttpWebRequest) WebRequest.Create(new Uri(curl));
ServicePointManager.Expect100Continue = false;
try
{
((HttpWebResponse) request.GetResponse()).Close();
}
catch (WebException exception)
{
if (exception.Status != WebExceptionStatus.ProtocolError)
{
return num;
}
if (exception.Message.IndexOf("500") > 0)
{
return 500;
}
if (exception.Message.IndexOf("401") > 0)
{
return 401;
}
if (exception.Message.IndexOf("404") > 0)
{
num = 404;
}
}
return num;
}
}
{
int num = 200;
if (this.method == 1)
{
HttpWebRequest request = (HttpWebRequest) WebRequest.Create(new Uri(curl));
ServicePointManager.Expect100Continue = false;
try
{
((HttpWebResponse) request.GetResponse()).Close();
}
catch (WebException exception)
{
if (exception.Status != WebExceptionStatus.ProtocolError)
{
return num;
}
if (exception.Message.IndexOf("500") > 0)
{
return 500;
}
if (exception.Message.IndexOf("401") > 0)
{
return 401;
}
if (exception.Message.IndexOf("404") > 0)
{
num = 404;
}
}
return num;
}
}
当搜索引擎在请求某个Url时得到“404”状态回应时,便会知道该网页在网站内不复存在,从而在索引数据库中将其删除,——当然,这个删除过程有 可能需要很长时间——而当搜索引擎得到“200”状态回应时,则会认为该url是有效的,并将其回到到索引数据库中。
关于HTTP状态码,请参见
http://seo.highdiy.com/index.php/seo/custom-404-pages-and-error-code/
以 前本人曾研究过SEO,但是发现,过于技术化的SEO反道不好了{不好意思,话说远了}
GetUrlError("http://www.csdn.net/images/logo_csdn.gif")//判断其返回值