怎样用C#检测一超级链的有效性？？？

Question

/// <summary>
/// GET方式发送请求
/// </summary>
/// <param name="requestUrl">请求地址</param>
/// <returns>响应字符串</returns>
public string SendRequest( string requestUrl )
{
HttpWebRequest httpWebRequest = ( HttpWebRequest ) WebRequest.Create( requestUrl );
httpWebRequest.Method = "GET";
WebResponse webResponse = httpWebRequest.GetResponse();
StreamReader responseStream = new StreamReader( webResponse.GetResponseStream(), System.Text.Encoding.UTF8 );
_responseStr = responseStream.ReadToEnd();
webResponse.Close(); 
responseStream.Close();
return _responseStr;
}
有响应则有效

Answer 1

Creating a Multi-threaded URL Status Checkerhttp://www.wwwcoder.com/main/DesktopDefault.aspx?tabid=68&mid=407&site=1883&parentid=177