pxt-calliope/docs/blocks/logic/if.md
Peli de Halleux 92b60a251d On start support ()
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2016-12-19 14:09:35 -08:00

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Markdown

# If
### @parent blocks/language
Conditionally run code depending on whether a [Boolean](/blocks/logic/boolean) condition is true or false.
```blocks
if(true) {
}
```
Click on the dark blue gear icon (see above) to add an *else* or *if* to the current block.
### Example: adjusting screen brightness
If the [light level](/reference/input/light-level) is `< 100`, this code sets the brightness to `255` when the button A is pressed:
```blocks
input.onButtonPressed(Button.A, () => {
if(input.lightLevel()<100){
led.setBrightness(255);
}
})
```
### See also
[while loop](/blocks/loops/while), [for](/blocks/loops/for), [boolean](/blocks/logic/boolean)