StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

POWhat is a proper implementation of the IAsyncResult interface?
text
Body
copied!<p>I'm looking into adding some flexibility to a class that I've created which establishes a connection to a remote host and then performs an exchange of information (a handshake). The current implementation provides a Connect function which establishes the connection and then blocks waiting on a ManualResetEvent untill the two parties have completed the handshake.</p> <p>Here's an example of what calling my class looks like:</p> <pre><code>// create a new client instance ClientClass cc = new ClientClass("address of host"); bool success = cc.Connect(); // will block here until the // handshake is complete if(success) { } </code></pre> <p>..and here's an oversimplified high-level view of what the class does internally:</p> <pre><code>class ClientClass { string _hostAddress; ManualResetEvent _hanshakeCompleted; bool _connectionSuccess; public ClientClass(string hostAddress) { _hostAddress = hostAddress; } public bool Connect() { _hanshakeCompleted = new ManualResetEvent(false); _connectionSuccess = false; // start an asynchronous operation to connect // ... // ... // then wait here for the connection and // then handshake to complete _hanshakeCompleted.WaitOne(); // the _connectionStatus will be TRUE only if the // connection and handshake were successful return _connectionSuccess; } // ... other internal private methods here // which handle the handshaking and which call // HandshakeComplete at the end private void HandshakeComplete() { _connectionSuccess = true; _hanshakeCompleted.Set(); } } </code></pre> <p>I'm looking into implementing the <a href="http://msdn.microsoft.com/en-us/library/ms228975.aspx" rel="noreferrer">.NET Classic Async Pattern</a> for this class. In doing so, I would provide BeginConnect and EndConnect functions, and allow the users of the class to write code like this:</p> <pre><code>ClientClass cc = new ClientClass("address of host"); cc.BeginConnect(new AsyncCallback(ConnectCompleted), cc); // continue without blocking to this line // .. void ConnectCompleted(IAsyncResult ar) { ClientClass cc = ar.AyncState as ClientClass; try{ bool success = cc.EndConnect(ar); if(success) { // do more stuff with the // connected Client Class object } } catch{ } } </code></pre> <p>In order to be able to provide this API I need to create a class that implements the IAsyncResult interface to be returned by the BeginConnect function, and to be passed into the EndConnect function respectively.</p> <p><strong>Now, my question is: What is a proper way to implement the IAsyncResult interface in a class?</strong></p> <p>One obvious solution would be to create a delegate with a matching signature for the Connect function and then invoke that delegate asynchronously using BeginInvoke - EndInvoke but that is not what I'm looking for (it's not very efficient).</p> <p>I have a rough idea of how I could do it but after peeking inside the .NET framework at how they implement this pattern in some places I felt it would be wise to ask and see if anybody has done this successfully and if so what are the problem areas to pay special attention to.</p> <p>Thanks!</p>

Querying!

Guidance

An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload