How to check identical array in most efficient way?

Question

Hi, I want to check if the two arrays are identical (not content wise, but in exact order).

For example:

 array1 = [1,2,3,4,5]
 array2 = [1,2,3,4,5]
 array3 = [3,5,1,2,4]

Array 1 and 2 are identical but 3 is not.

Is there a good way to do this in JavaScript?

Answer 1

array1_matches_array2 = array1.join() === array2.join(); // true
array1_matches_array3 = array1.join() === array3.join(); // false

updated: default arg for join is ","

Answer 2

You might want to check Compare two Arrays Javascript - Associative

Answer 3

Sort the arrays and then compare them.

array1.sort() == array2.sort();

Answer 4

You could compare String representations so:

array1.toString() == array2.toString()
array1.toString() !== array3.toString()

but that would also make

array4 = ['1',2,3,4,5]

equal to array1 if that matters to you

Answer 5

So, what's wrong with checking each element iteratively?

function arraysEqual(arr1, arr2) {
    if(arr1.length !== arr2.length)
        return false;
    for(var i = arr1.length; i--;) {
        if(arr1[i] !== arr2[i])
            return false;
    }

    return true;
}