An application sends the EM_SETWORDBREAKPROC message to an edit control to replace the default wordwrap function with an application-defined wordwrap function.
EM_SETWORDBREAKPROC wParam = 0; // not used; must be zero lParam = (LPARAM)(EDITWORDBREAKPROC)ewbprc; // function address
This message does not return a value.
A wordwrap function scans a text buffer that contains text to be sent to the screen, looking for the first word that does not fit on the current screen line. The wordwrap function places this word at the beginning of the next line on the screen.
A wordwrap function defines the point at which Windows should break a line of text for multiline edit controls, usually at a space character that separates two words. Either a multiline or a single-line edit control might call this function when the user presses arrow keys in combination with the CTRL key to move the caret to the next word or previous word. The default wordwrap function breaks a line of text at a space character. The application-defined function may define the wordwrap to occur at a hyphen or a character other than the space character.