An application sends a ZGM_INTERPRETBOOL message to enable or disable the interpretation of the text 'TRUE' and 'FALSE' as boolean when entered from an editable cell by the user, or programmatically entered into the cell with the ZGM_SETCELLTEXT message.
ZGM_INTERPRETBOOL
wParam = (WPARAM) (BOOL) fEnable; //enable flag
lParam = 0; //not used; must be zero
This message does not return a value.
Interpret boolean is enabled by default.
When enabled, the entered text is converted to uppercase and tested for a match with 'TRUE' or 'FALSE'. Therefore, the text strings 'True','trUE', and 'TrUe' would all be interpreted as boolean.