An application sends an EM_SETREADONLY message to set or remove the read-only style (ES_READONLY) of an edit control.
EM_SETREADONLY
wParam = (WPARAM) (BOOL) fReadOnly; // read-only flag
lParam = 0; // not used; must be zero
Parameters
fReadOnly
Value of wParam. Specifies whether to set or remove the ES_READONLY style. A value of TRUE sets the ES_READONLY style; a value of FALSE removes the ES_READONLY style.
Return Values
If the operation succeeds, the return value is nonzero; otherwise, it is zero.
Remarks
When an edit control has the ES_READONLY style, the user cannot change the text within the edit control.
To determine whether an edit control has the ES_READONLY style, use the GetWindowLong function with the GWL_STYLE flag.
See Also