Go homepage(回首页) Upload pictures (上传图片) Write articles (发文字帖)
The author:(作者)delvpublished in(发表于) 2014/1/23 3:11:37 ASP.NET实例：检测远程URL是否存在的三种方法_[Asp.Net教程]
本文用3种方法检测远程URL是否存在。
private void Page_Load(object sender, System.EventArgs e){
string url1 = "/"; string url2 = "/Images/logo1.gif"; Response.Write("方法1："); Response.Write(url1 + " 存在：" + UrlExistsUsingHttpWebRequest(url1).ToString()); Response.Write("方法2："); Response.Write(url1 + " 存在：" + UrlExistsUsingSockets(url1).ToString()); Response.Write("方法3："); Response.Write(url1 + " 存在：" + UrlExistsUsingXmlHttp(url1).ToString());
Response.Write("方法1："); Response.Write(url2 + " 存在：" + UrlExistsUsingHttpWebRequest(url2).ToString()); Response.Write("方法3："); Response.Write(url2 + " 存在：" + UrlExistsUsingXmlHttp(url2).ToString());}private bool UrlExistsUsingHttpWebRequest(string url){ try { System.Net.HttpWebRequest myRequest =(System.Net.HttpWebRequest)System.Net.WebRequest.Create(url); myRequest.Method = "HEAD"; myRequest.Timeout = 100; System.Net.HttpWebResponse res = (System.Net.HttpWebResponse)myRequest.GetResponse(); return (res.StatusCode == System.Net.HttpStatusCode.OK); } catch(System.Net.WebException we) { System.Diagnostics.Trace.Write(we.Message); return false; }}private bool UrlExistsUsingXmlHttp(string url){ //注意：此方法需要引用Msxml2.dll MSXML2.XMLHTTP _xmlhttp = new MSXML2.XMLHTTPClass(); _xmlhttp.open("HEAD",url,false,null,null); _xmlhttp.send(""); return (_xmlhttp.status == 200 );}
private bool UrlExistsUsingSockets(string url){ if(url.StartsWith("http://")) url = url.Remove(0,"http://".Length); try { System.Net.IPHostEntry ipHost = System.Net.Dns.Resolve(url); return true; } catch (System.Net.Sockets.SocketException se) { System.Diagnostics.Trace.Write(se.Message); return false; }}
赞