What is the length of the array here?

Question

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HTML

<!DOCTYPE html>
<html>
	<head>
		<title>Page Title</title>
	</head>
	<body>
		<p>hi</p>
        <p>hello</p>
        <p>hi</p>
        <script>
            var arr = document.getElementsByTagName("p");
            for (var x = 0; x < arr.length; x++) {
                arr[x].innerHTML = "Hi there";
            }
        </script>
	</body>
</html>

What I have tried:

Isn't the length of the array (arr.length) equal to 1, since there's only 1 element "p"? So how does this condition work in this code if x can only be less than the array's length?

Posted 22-Nov-17 6:41am

Member 13502831

Updated 22-Nov-17 7:43am

PIEBALDconsult

v2

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CPallini · Accepted Answer · 2017-11-22T07:02:00

Actually there are three p elements. Try

JavaScript

<!DOCTYPE html>
<html>
	<head>
		<title>Page Title</title>
	</head>
	<body>
		<p>hi</p>
        <p>hello</p>
        <p>hi</p>
        <script>
            var arr = document.getElementsByTagName("p");
            for (var x = 0; x < arr.length; x++) {
                arr[x].innerHTML = "Hi there " + arr[x].textContent;
            }
        </script>
	</body>
</html>

F-ES Sitecore · Accepted Answer · 2017-11-22T07:05:00

getElementsByTagName("p") gets all <p> elements, and there are three p elements, "hi", "hello" and the second "hi", so arr.length will be 3, so x will loop through 0, 1, then 2, as javascript arrays are accessed on a zero-base so 0 is the first, 2 the third, so it will set the innerHTML of all three elements.

What is the length of the array here?

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