pxt-calliope/docs/reference/input/button-is-pressed.md

Button Is Pressed

Check whether a button is pressed right now. The micro:bit has two buttons: button A and button B.

input.buttonIsPressed(Button.A);

Parameters

• button is a String. You should store A in it to check the left button, B to check the right button, or A+B to check both at the same time.

Returns

• Boolean that is true if the button you are checking is pressed, false if it is not pressed.

Example

This program uses an if to run one part of the program if the A button is pressed, and another part if it is not pressed.

basic.forever(() => {
    let pressed = input.buttonIsPressed(Button.A)
    if (pressed) {
        // this part runs if the A button is pressed
        basic.showNumber(1, 150)
    } else {
        // this part runs if the A button is *not* pressed
        basic.showNumber(0, 150)
    }
})

See also

on button pressed, if, forever