Run only once inside a loop

Running script only once inside a loop in JavaScript:

HTML code:

<div class="example">
	<div>element 1</div>
	<div>element 2</div>
	<div>element 3</div>
</div>

JavaScript code:

<script>
var is_run = 0;
var elements = document.querySelectorAll('.example div');

for ( var element of elements ) {
	if ( is_run == 0 ) {
		element.classList.add('red');
		is_run = 1;
	}
}
</script>

Browser support

Windows

Edge 12.0+

Firefox 13.0+

Google Chrome 38.0+

Opera 25.0+

Linux

Firefox 13.0+

Google Chrome 38.0+

Opera 25.0+

iOS

Safari 7.0+

Android

Samsung Internet 3.0+

Chrome 38.0+

Firefox 14.0+

Opera 25.0+

More

• Accessing the first element in forEach loop (JavaScript)
• How to call a function multiple times (JavaScript)