Comparing object variables within Javascript's HTMLCollection

let var1, var2;

// Obtaining elements from the HTMLCollection

var1 = document.forms[0];
var2 = document.forms.item(0);

alert(var1 === var2); // Output: "true"

var1 = document.forms["myForm"];
var2 = document.forms.namedItem("myForm");

alert(var1 === var2); // Output: "true"

Source: https://developer.mozilla.org/en-US/docs/Web/API/HTMLCollection

In the provided code snippet, variables var1 and var2 both refer to the same object, specifically a DOM node

I am curious about what exactly is compared in the statement var1 === var2 to result in a TRUE value. Is it the nodeType, nodeValue, or nodeName?

Answer №1

Not any of the options listed.

When using the === operator, it specifically evaluates for reference equality.
This means it will only yield true if both expressions are referring to the exact same object.

Answer №2

There is no actual comparison of properties. Both elem1 and elem2 serve as references to objects, with both variables pointing to the same object.

In this scenario, you could have also utilized the == operator. The === operator goes a step further by checking for the type of the argument as well.

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