How to detect a Socket Disconnect in C#

Question

I'm working on a client/server relationship that is meant to push data back and forth for an indeterminate amount of time.

The problem I'm attempting to overcome is on the client side, being that I cannot manage to find a way to detect a disconnect.

I've taken a couple of passes at other peoples solutions, ranging from just catching IO Exceptions, to polling the socket on all three SelectModes. I've also tried using a combination of a poll, with a check on the 'Available' field of the socket.

// Something like this
Boolean IsConnected()
{
    try
    {
        bool part1 = this.Connection.Client.Poll(1000, SelectMode.SelectRead);
        bool part2 = (this.Connection.Client.Available == 0);

        if (part1 & part2)
        {
            // Never Occurs
            //connection is closed
            return false;
        }
        return true;
    }
    catch( IOException e )
    {
        // Never Occurs Either
    }
}

On the server side, an attempt to write an 'empty' character ( \0 ) to the client forces an IO Exception and the server can detect that the client has disconnected ( pretty easy gig ).

On the client side, the same operation yields no exception.

// Something like this
Boolean IsConnected( )
{
    try
    {

        this.WriteHandle.WriteLine("\0");
        this.WriteHandle.Flush();
        return true;
    }
    catch( IOException e )
    {
        // Never occurs
        this.OnClosed("Yo socket sux");
        return false;
    }
}

A problem that I believe I am having in detecting a disconnect via a poll, is that I can fairly easily encounter a false on a SelectRead, if my server hasn't yet written anything back to the client since the last check... Not sure what to do here, I've chased down every option to make this detection that I can find and nothing has been 100% for me, and ultimately my goal here is to detect a server (or connection) failure, inform the client, wait to reconnect, etc. So I am sure you can imagine that this is an integral piece.

Appreciate anyone's suggestions. Thanks ahead of time.

EDIT: Anyone viewing this question should note the answer below, and my FINAL Comments on it. I've elaborated on how I overcame this problem, but have yet to make a 'Q&A' style post.

How to detect a Socket Disconnect in C#

1 Answers