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

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# Button Is Pressed
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Check whether a button is pressed right now. The @boardname@ has two buttons: button `A` and button `B`.
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```sig
input.buttonIsPressed(Button.A);
```
### Parameters
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* ``button`` is a [String](/reference/types/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.
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### Returns
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* [Boolean](/blocks/logic/boolean) that is `true` if the button you are checking is pressed, `false` if it is not pressed.
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### Example
This program uses an [if](/blocks/logic/if) to run
one part of the program if the `A` button is pressed, and
another part if it is not pressed.
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```blocks
basic.forever(() => {
let pressed = input.buttonIsPressed(Button.A)
if (pressed) {
// this part runs if the A button is pressed
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basic.showNumber(1, 150)
} else {
// this part runs if the A button is *not* pressed
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basic.showNumber(0, 150)
}
})
```
### See also
[on button pressed](/reference/input/on-button-pressed), [if](/blocks/logic/if), [forever](/reference/basic/forever)
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