JavaScript Interview Question 43: Object.toString vs Array.toString

What's the difference between Object.toString and Array.toString in JavaScript? Whats the output?

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A regular behavior of the JavaScript function Object.prototype.toString in a browser is a string that looks like [object "TYPE"]. The part "TYPE" is substituted with the type of the Object that toString is called on. In our case, it's Array.

console.log(toStringObj.call(arr)); // [object Array]

In the second instance, we call toString from Array. Its not the same function as it overrides the standard implementation of Object.prototype.toString.

Array.prototype.toString returns a string that consists of all the array elements separated with commas.

console.log(toStringArr.call(arr)); // 1,2,3

ANSWER: 2 strings will appear on the screen:

[object Array]1,2,3

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