Socket closed

[sunburnt]

I posted this a while ago, but I can't seem to get an answer or find one elsewhere. Anyway, how does one know when a NetworkStream or TcpClient's connection is closed? Right now I'm doing something like this:

try
{
    while(_nstream != null)
    {
       //read / write
    }
}
catch
{
   // socket closed?
}

but this never seems to work. the connection will be terminated by the remote host, but you wouldn't know it... any suggestions?