public bool pingNetworkStatus()
{
	try
	{
		Ping a = new Ping();
		PingReply re = a.Send("baidu.com");
 
		return (re.Status == IPStatus.Success);
	}
	catch (Exception e)
	{
		Console.WriteLine(e.Message);
	}
	return false;
}

以往查看网络是否有连接是打开浏览器看看能不能打开百度~~没想到用代码也是这么搞的:-)