In JavaScript, what's the difference between myArray.length = 0 vs myArray = new Array()?

Regarding JavaScript, when clearing an array, I've found two methods:

myArray.length = 0;

vs

myArray = new Array()

I would guess logically myArray.length = 0; keeps the reference while myArray = newArray() creates a new reference making previous references void.

However, I have found in the past guessing how JavaScript works by using my own logic has been regularly unsuccessful :)

What's the difference (if any) between the two methods?

Answer

You are correct this time. new Array() creates a new instance of array and assign it to myArray.
myArray.length = 0 empties an old array while myArray still points to the old array.

Btw, it is better to use [] notation than new Array().

I personally always try to use myArray.length = 0; since it actually empties the content of the array.