To complement Simon Horrell's MSDN article on messaging with WSE 2.0, I came across this CodeProject article by Roman Kiss describing the three levels of messaging within WSE 2.0 as part of his MSMQ custom transport for WSE 2.0. This is an excellent bit of detective work (reflectoring, as they say) as there has not been much written about WSE 2.0's SoapTransport and it's in-memory queue that exist at the lowest level of the WSE messaging stack.
The benefit of the channel/queue model is that the message receiver can retrieve messages from the queue as they are ready to process them, rather than having to process them on demand.
Here's a simple example based on a Windows Forms application that has a button that can be clicked to retrieve messages from the in memory queue and display them in ListBox.
private
ISoapInputChannel channel = null;
private void Form1_Load(object sender, System.EventArgs e)
{
// Get our channel that's listening for incoming messages
channel = SoapTransport.StaticGetInputChannel(
new Uri("soap.tcp://localhost:8088/admin"),
SoapChannelCapabilities.ActivelyListening);
}
private
void button1_Click(object sender, System.EventArgs e)
{
// When we're ready, process the messages off the in-memory queue
SoapEnvelope message = channel.Receive();
String messageBody =
message.GetBodyObject(typeof(String)) as String;
this.listBox1.Items.Add( messageBody );
}
In the Form_Load event the channel is retrieved from the SoapTransport.StaticGetInputChannel method, based on the channel listening on a particular network address (in this case using tcp) with particular capabilities (the options are ActivitelyListening, meaning the channel should create a listener at that address, or None, meaning the channel should connect to an existing listener). As messages are received they are placed in an in-memory queue managed by this channel. When the Button_Click event is fired the next message can be retrieved from the channel by calling the Receive() method which returns a SoapEnvelope from which the body can be unpacked.