Did you look at the Ping class? (in System.Net.NetworkInformation)

If you want a general API, IsInternetConnected will do it:
http://msdn2.microsoft.com/en-us/library/aa366143(VS.85).aspx
but for a specific site you'd need another test, like ping.

What are you trying to do? For example a ping to a specific location will
tell you about a physical connection, but opening a browser window to it can
fail if IE has phishing or security blocking of that site.

I hacked up this little helper class that will allow you to check if you're
connected to the internet without having to ping a specific site.  The
method you need to call is NetUtils.IsConnectedToInternet().

/// <summary>
/// A collection of network related methods.
/// </summary>
public class NetUtils
{

/////////////////////
// Imported functions
[DllImport("wininet.dll")]
private extern static bool InternetGetConnectedState
(out int nDescription,
int nReserved);

/////////////
// Operations
/// <summary>
/// Checks if a connection to the internet exists.
/// </summary>
/// <returns>true if a connection to the internet exists.</returns>

public static bool IsConnectedToInternet()
{
int nDesc = 0;
if (!InternetGetConnectedState (out nDesc, 0))
return (false);
return (true);
}
}

Cheers,

/ravi

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