An application sends an EM_SETSEL message to select a range of characters in an edit control.
wParam = (WPARAM) (INT) nStart; // starting position
lParam = (LPARAM) (INT) nEnd; // ending position
Value of wParam. Specifies the starting character position of the selection.
Specifies the ending character position of the selection.
This message does not return a value.
In a rich edit control, if the selection is not entirely contained in the first 64K, use the message EM_EXSETSEL.
If the nStart parameter is 0 and the nEnd parameter is –1, all the text in the edit control is selected. If nStart is –1, any current selection is removed. The caret is placed at the end of the selection indicated by the greater of the two values nEnd and nStart.