/**
* callback function that writes in_message out to the response stream
* of client with ID in_key.
*/
public void Callback( string in_message, string in_key ) {
CallbackContext context = Callbacks[ in_key ];
System.Diagnostics.Trace.WriteLine( "calling callback with message " + in_message );
/*
* note that IsClientConnected doesn't get set until there has been a failure
* so the first time we try to write to disconnected response will result in first chance exception
* that we can't catch here for some reason
*/
if( context.Context.Response.IsClientConnected ) {
context.Context.Response.Write( "<p>CallBack: Thread " + Thread.CurrentThread.ManagedThreadId + " " + in_message + "</p>" );
flush( context.Context );
}
else {
m_keysFlaggedForDeletion.Add( in_key );
}
}
/*
* BeginProcessRequest gets called automatically when the request comes in
* We don't have to handle things in ProcessRequest/PageLoad and then set
* everything up manually using RegisterAsyncTask like we do with an async
* aspx page. We ignore
*/
public IAsyncResult BeginProcessRequest( HttpContext context, AsyncCallback callback, Object extraData ) {
context.Response.Write( "<p>BeginProcessReqeust: Thread " + Thread.CurrentThread.ManagedThreadId + "</p>" );
// async is a dummy IAsyncResult to satisfy the method signature
AsyncOperation async = new AsyncOperation( null, null, null );
// Callback context holds a callback and the httpcontext.
// In hindsight we could have done this without the callback
// so this is a possible point of refactoring. (TODO)
CallbackContext callbackContext = new CallbackContext(
new NotificationCallback( Callback ),
context
);
/**
* TODO: this is too coarse of a lock, should be locking 'callbacks'
*/
lock( typeof( Register ) ) {
Callbacks.Add( Guid.NewGuid().ToString(), callbackContext );
}
return async;
}