On Button Pressed

Start an event handler (part of the program that will run when something happens, like when a button is pressed). This handler works when button A or B is pressed, or A and B together. When you are using this function in a web browser, click the buttons on the screen instead of the ones on the micro:bit.

For button A or B: This handler works when the button is pushed down and released within 1 second.
For A and B together: This handler works when A and B are both pushed down, then one of them is released within 1.5 seconds of pushing down the second button.

input.onButtonPressed(Button.A, () => {})

Find out how buttons provide input to the micro:bit in this video:

Example: count button clicks

This example counts how many times you press the A button. Each time you press the button, the LED screen shows the count variable getting bigger.

let count = 0 basic.showNumber(count) input.onButtonPressed(Button.A, () => { count++; basic.showNumber(count); })

Example: roll dice

This example shows a number from 1 to 6 when you press the B button.

input.onButtonPressed(Button.B, () => { let dice = randint(0, 5) + 1 basic.showNumber(dice) })

This program adds a 1 to random(5) so the numbers on the dice will come out right. Otherwise, sometimes they would show a 0.

On Button Pressed

Example: count button clicks

Example: roll dice

See also