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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Build a Quiz Challenge, Part 1

Two Dimenstional Arrays

what does the Array.length property returns in case of 2d arrays i know it returns the length but it is a bit confusing could some one explain please ?

5 Answers

Balazs Peak
Balazs Peak
46,121 Points

Think of it like this: multi dimensional arrays are actually not multi dimensional, they are just "recursive".

A 2 dimensional array is an array of arrays. A 3 dimensional array is an array of arrays of arrays ... etc.

The length property returns the outer-most dimension's length.

Balazs Peak
Balazs Peak
46,121 Points

It will return the length of the first dimension.

I've made a demonstration with a 2 dimensional and a 1 dimansional array, check it out:


the first dimension is the row you mean ??

Aha Thanks a lot i got it