This case is so commonplace there can be a work entitled PostQuitMessage to post WM_Stop. PostMessage usually works better when you wish in order to replicate a demand otherwise enter in event because of the post WM_Demand or one of several guitar otherwise mouse messages (that is always dicey, incidentally). That it holds true since „real” enter in incidents always are located in sequences off relevant texts (such as for example keydown/keyup pairs) as well as your app gets befuddled if you attempt to help you process a new input message in the middle of one of those sequences. Article increases results when simulating type in. Sometimes you have to play with PostMessage locate up to a good quirk otherwise bug to avoid unlimited recursion. Like, guess the WM_SETFOCUS handler (OnSetFocus) identifies that the the newest notice screen is not best for some reasoning along with to change the main focus to another window.
For people who telephone call SetFocus from inside their OnSetFocus handler, Window instantly delivers some other WM_SETFOCUS messagea€”while you are nonetheless running the first you to definitely!
The result is unlimited regress up until your own stack blows upwards. To get rid of so it infelicity, you might blog post an email so you can yourselfa€”MYWM_SWITCHFOCUSa€”thus OnSetFocus can be end one which just process the message adjust the main focus. This is one of those advice that is better to understand when you look fransk kone at the routine than on paper. What is very important to keep in mind is that Screen would not allow you to SetFocus within this a good WM_SETFOCUS handler. Once the SendMessage phone calls the fresh window proc yourself, it entails an HWND. How else does it understand and this content proc to name? But PostMessage contributes the message for the content waiting line, which is of a bond or processes, not a windows.
// article content to mePostMessage(NULL, WM_HI_THERE_Good-looking, . );
That is, they tries to end up being sweet by providing for every software a spin to die gracefully, however, if an application does not act over time, ExitWindowsEx eliminates the app anyhow
Whether your HWND is actually NULL, PostMessage postings the content to the current powering thread’s content waiting line. Used, this feature is not defectively useful since the majority moments we need to blog post a contact to another bond (perhaps having PostThreadMessage); however, you can find always unusual activities when it’s simpler to publish in order to on your own rather than a windows. (If you feel of any, please let me know.) Should you imagine you’re begin to see when to use SendMessage and you can PostMessage, you’ll find around three so much more message-giving characteristics you should know throughout the: SendMessageCallback, SendNotifyMessage, and you will SendMessageTimeout. Such features are of help in the heady world of Win32A® and you can multithreading. When you look at the Win32, for individuals who name SendMessage the thread was prohibited before address thread process the message. In case the address thread was itself prohibited for most most other cause, SendMessage never ever returns. Oops. SendNotifyMessage, SendMessageTimeout, and you may SendMessageCallback were created to be effective around this state. SendNotifyMessage really works such as for instance SendMessage when your address screen belongs to (is made because of the) the current bond; it really works for example PostMessage if your windows is part of a separate thread. SendMessageTimeout is similar, nonetheless it lets you specify a maximum time for you to watch for others bond to respond. Also crappy, therefore sad. SendMessageTimeout delays, but not forever. Because you you will assume, SendMessageCallback takes an excellent callback means. It delivers the content and production quickly; when the content might have been processed, Window calls the function. SendMessageCallback is available in helpful when you want to play with PostMessage, nevertheless want to know in the event the message might have been handled. Consider it because the PostMessage having income bill. PostMessage, SendMessageTimeout, and you can SendNotifyMessage are all good people to make use of if you’d like to transmitted a contact to all better-peak window that with HWND_TOPMOST because HWND. It’s an awful idea to utilize HWND_TOPMOST having SendMessage because that lifeless process brings the app to help you a stop. Profile 2 sumong various message-sending attributes. Whew!