分析源代码下载远程图片 c#

关于webreuqust不能定义超时！的问题

HttpWebRequest request = null;
try
{
request = (HttpWebRequest)WebRequest.Create(strLink);
request.UserAgent = “Mozilla/5.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1;.NET CLR 2.0.50727)”;
return request.GetResponse().GetResponseStream();
}
catch
{
return null;
}