What is Window Message coded 641?

Not sure what this code 641 indicates. Does anybody know how to reverse look up meaning of this code?

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I also looked up in header file and notice there is WM_IME_SETCONTEXT = 641, but not sure what it is to do with my application.

I have a CListCtrl in GUI, and draw a CEdit control over its cell when the cell is double-clicked. When CEdit control in focus, I press 'ESC', CEdit control focus killed, but CListCtrl columns and rows disappear entirely after it receives this message. Maybe I missed some other details.

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What I have done as a solution is to handle 'ESC' key in my edit control's OnKeyDown() handler, simply hide edit control window, thus no further message sent to parent control. I guess 'ESC' key must c开发者_如何学编程ause some window invalidation like message. But I don't know why it propagates to parent.

It's WM_IME_SETCONTEXT. I don't know of a good way to look these up except for grepping the SDK headers for the number or hex number; from WinUser.h:

#define WM_IME_SETCONTEXT               0x0281

This doesn't always work for Windows enums as they can be defined as (OTHER_CONSTANT + 1) etc. Thankfully the worst set of these, the error message codes, have a lookup util err.exe in the Platform SDK.

You're going to get messages you don't recognize. The correct way to handle them is by forwarding to DefWindowProc.