Console messages windows

However, because MessageWindow is a nested class within MessageEvents, MessageWindow does have access to the private implementation details of MessageEvents. In this case, that allows MessageWindow access to the private MessageReceived delegate, allowing it to be invoked directly by MessageWindow. The SynchronizationContext is used to raise the event through an asynchronous Post rather than a synchronous Send in the synchronization context of the application, whatever that may be.

In a console application, SynchronizationContext. Post simply executes the delegate on a ThreadPool thread. Post executes the delegate by marshaling its invocation back to the UI thread.

For more information on SynchronizationContext, see msdn. The MessageEvents class only contains static members, and in fact the class itself is declared as a static class the compiler will complain if an attempt is made to add a non-static member.

Internally, it stores a static reference to a single MessageWindow that is created when MessageEvents is initialized:. The WindowHandle property also calls EnsureInitialized and simply returns the window handle created during initialization:. That leaves us with how to implement EnsureInitialized. EnsureInitialized is responsible for getting the MessageEvents class up and running so that it can watch for and respond to all relevant messages.

Thus, it needs to spawn off a new thread, create the broadcast window that will receive messages, and start a message loop running. As shown in Figure 2 , EnsureInitialized only runs the initialization logic once; if it sees that the MessageWindow has already been created, it bails. If initialization needs to be performed, it starts by grabbing the SynchronizationContext associated with the current thread.

It could do this using SynchronizationContext. Current; however, SynchronizationContext. This includes the target window and the message code. The other three parameters let you filter which messages you get from the queue. In almost all cases, you will set these parameters to zero. Although the MSG structure contains information about the message, you will almost never examine this structure directly.

Instead, you will pass it directly to two other functions. The TranslateMessage function is related to keyboard input. It translates keystrokes key down, key up into characters. You do not really have to know how this function works; just remember to call it before DispatchMessage. The link to the MSDN documentation will give you more information, if you are curious. The DispatchMessage function tells the operating system to call the window procedure of the window that is the target of the message.

In other words, the operating system looks up the window handle in its table of windows, finds the function pointer associated with the window, and invokes the function. When the window procedure returns, it returns back to DispatchMessage. This returns to the message loop for the next message. As long as your program is running, messages will continue to arrive on the queue.

Therefore, you must have a loop that continually pulls messages from the queue and dispatches them. You can think of the loop as doing the following:.

As written, of course, this loop would never end. ReadConsoleInput is to read data from a console buffer input from keyboard. Are you writing a console app or a windowed app? Your question sounds like you have a console app, but the sample code looks like a windowed app.

What is the scenario that you are trying to achieve here? Why do you need to know what is happening to the console host window? Windowed apps don't have any link to the console window, even if they were launched from a command line. I'm not clear what you are trying to do with the message only window here.

Message only windows don't do anything related to what I think you want. Message only windows are designed to limit the messages that the app receives to ones directly targeting it.

They won't help to intercept messages aimed at other windows. Asked 11 years, 8 months ago. Active 10 years, 10 months ago. Viewed 4k times. Any ideas?

Improve this question. Vicken Simonian Vicken Simonian 4 4 silver badges 6 6 bronze badges. Did you put the message pump on the same thread as your CreateWindow call?

Just curious, What kind of Win32 messages do you need from a Console App? Thanks Gabe. Add a comment. Active Oldest Votes.