.net 怎么检测到网页是否连接成功
各位,
用VB.net 怎么判断是否连接到网站上的一个网页?
比如,要测试连接上http://www.XXX.com/connection_text.html
如果连接成功,则返回一个值,如果连接失败,返回另一个值.
请问如何处理?
[解决办法]
using System;
using System.Net;
static class Program
{
static void Main()
{
using (MyClient client = new MyClient())
{
client.HeadOnly = true;
string uri = "http://www.google.com";
byte[] body = client.DownloadData(uri); // note should be 0-length
string type = client.ResponseHeaders["content-type"];
client.HeadOnly = false;
// check 'tis not binary... we'll use text/, but could
// check for text/html
if (type.StartsWith(@"text/"))
{
string text = client.DownloadString(uri);
Console.WriteLine(text);
}
}
}
}
class MyClient : WebClient
{
public bool HeadOnly { get; set; }
protected override WebRequest GetWebRequest(Uri address)
{
WebRequest req = base.GetWebRequest(address);
if (HeadOnly && req.Method == "GET")
{
req.Method = "HEAD";
}
return req;
}
}
