How to detect whether internet is availabe in a system or not using C#.Net?

protected bool IsNetworkConnected()
{
bool connected = false;
System.Management.ManagementObjectSearcher searcher = new System.Management.ManagementObjectSearcher("SELECT NetConnectionStatus FROM Win32_NetworkAdapter");
foreach (System.Management.ManagementObject networkAdapter in searcher.Get())
{
if (networkAdapter["NetConnectionStatus"] != null)
{
if (Convert.ToInt32(networkAdapter["NetConnectionStatus"]).Equals(2))
{
connected = true;
break;
}
}
}
searcher.Dispose();
return connected;
}
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OR
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public bool IsConnectionAvailable()
{
System.Net.WebRequest objWebReq= System.Net.WebRequest.Create("http://www.kannabiranb.blogspot.com/");
System.Net.WebResponse objResp;
try
{
objResp = objWebReq.GetResponse();
objResp.Close();
objWebReq = null;
return true;
}
catch(Exception ex)
{
objResp = null;
objWebReq = null;
return false;
}
}