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

Posted by Mahmoud Nasser
Mahmoud Nasser
5,507 Points

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
46,160 Points
Balazs Peak
Balazs Peak
46,160 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
46,160 Points
Balazs Peak
Balazs Peak
46,160 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:

http://rextester.com/LKGB89866

Mahmoud Nasser
Mahmoud Nasser
5,507 Points
Mahmoud Nasser
Mahmoud Nasser
5,507 Points

the first dimension is the row you mean ??

Mahmoud Nasser
Mahmoud Nasser
5,507 Points
Mahmoud Nasser
Mahmoud Nasser
5,507 Points

Aha Thanks a lot i got it