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cwinapidialognotepadeditcontrol

How to disable pasting words into a number-only edit control?

I am writing in C WinAPI a 'Go To Line' dialog of the notepad. I created a number only edit control. But I can still paste words into the edit control! The dialog in the windows notepad does stop this kind of pasting. So how can I do the same thing as it in the notepad?

Solution

  • Subclass the edit control, and when WM_PASTE is received:

    OpenClipboard
GetClipboardData
GlobalLock

    Now use the returned pointer from GlobalLock to check for non numeric characters. If a non number is found, inform user then:

    GlobalUnlock
CloseClipboard

    and return 0 from the callback to prevent pasting the data into the edit control.

    If it is all numbers, then GlobalUnlock and CLoseClipboard and pass message on with CallWindowProc to allow paste.