Understanding the DOM

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OK, guys, this one is driving me nuts. I'm doing a little bit of Javascript studying and trying to understand how the JS is resolving this. Here's the code fragment:

<!DOCTYPE html> 
<html>
	<head>
		<title>JavaScript Programmer's Reference</title>
	</head>
	<body>
		<p id="myParagraph">This is my paragraph! <span class="hideme1">Lorem ipsum</span> dolor sit amet.
			<span></span>
		</p>
		<p class="hideme2">Another paragraph!</p>
		<script>
			alert(document.childNodes[1].childNodes[2].childNodes[3].className);  // will alert "hideme2"
		</script>
    </body>
</html>

Now, if the HTML (DOM?) is organized in a tree then how does the reference "document.childNodes[1].childNodes[2].childNodes[3] get us to that 2nd paragraph in the body? The alert displays 'hideme2'.

I can see that DOCTYPE is document.childNodes[0] and the HTML block is document.childNodes[1]. I would expect , then to be document.childNodes[1].childNodes[1], right? I don't see how there is even a document.childNodes[1].childNodes[2], let alone a 3rd level under it.

I'm obviously missing something here but only see 3 elements that are subordinate to the body, 2 paragraphs and the block. I would expect the 2nd paragraph to, then, be document.childNodes[1].childNodes[1].childNodes[1] (Assuming everything is 0-based, as usual). What am I not seeing here?

Thanks,

CM

<b>What I have tried:</b>

Scratching my head and studying DOM references.

Posted 2-Oct-18 6:31am

ClockMeister

Updated 3-Oct-18 5:59am

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Richard Deeming · Answer 1 · 2018-10-03T05:59:00

Try using the browser's developer tools. Firefox has a DOM explorer which might help. Alternatively, this online DOM viewer[^] works pretty well.

document.childNodes:
    [0] = <!DOCTYPE html>
    [1] = <html>
        .childNodes:
            [0] = <head>
            [1] = #whitespace#
            [2] = <body>
                .childNodes:
                    [0] = #whitespace#
                    [1] = <p id="myParagraph">
                    [2] = #whitespace#
                    [3] = <p class="hideme2">

https://javascript.info/dom-nodes[^]