The _BUTTON function returns -1 when specified button number on a controller device is pressed.
Syntax
press%% = _BUTTON(button_number%)
Description
- The _DEVICEINPUT function should be read first to specify which device _BUTTON is intended to check.
- Values returned are -1 for a press and 0 when a button is released or not pressed.
- The button_number% must be a number which does not exceed the number of buttons found by the _LASTBUTTON function.
- The number of _DEVICES must be read before using _DEVICE$, _DEVICEINPUT or _LASTBUTTON.
- Note: The number 2 button is the center button in this device configuration. Center is also designated as _MOUSEBUTTON(3).
Example(s)
Reading multiple controller device buttons, axis and wheels.
FOR i = 1 TO _DEVICES
PRINT STR$(i) + ") " + _DEVICE$(i) + " Buttons:"; _LASTBUTTON(i); ",Axis:"; _LASTAXIS(i); ",Wheel:"; _LASTWHEEL(i)
NEXT
DO
d& = _DEVICEINPUT
IF d& THEN ' the device number cannot be zero!
PRINT "Found"; d&;
FOR b = 1 TO _LASTBUTTON(d&)
PRINT _BUTTONCHANGE(b); _BUTTON(b);
NEXT
FOR a = 1 TO _LASTAXIS(d&)
PRINT _AXIS(a);
NEXT
FOR w = 1 TO _LASTWHEEL(d&)
PRINT _WHEEL(w);
NEXT
PRINT
END IF
LOOP UNTIL INKEY$ = CHR$(27) 'escape key exit
END
Note: When there is no device control to read, a FOR…NEXT n = 1 TO 0 loop will not run thus avoiding a control function read error.