How to check all items match in an array using javascript/jQuery

Question

I would like to have a function in javascript (jQuery if possible) that will allow me to pass an array of ids into a function, and check if each value is found in another array to return TRUE.

e.g

var ids1 = [1, 6, 9, 11, 20];
var ids2 = [5, 6, 9, 11];

function check_array(ids)
{
    var search = [1, 6, 9, 11, 20];
    // do some checking here

    // if all ids are matched up return TRUE; 

    // otherwise return FALSE;
}

In this instance - the first var ids1 would return TRUE, while the second var ids2 would return FALSE.

Can anyone suggest the simplest/cleanest method for this?

I didn't try myself purely as I thought that they might be a javascript function that already does this that I am not aware e.g. array_diff() in PHP would allow me to do this, I wondered if javascript had a similar function — Zabs, Jun 25 '13 at 12:59

score 2 · Accepted Answer · answered Jun 25 '13 at 12:59

function check_array(ids1, ids2) {
    return $(ids1).not(ids2).get().length === 0;
}

var ids1 = [1, 6, 9, 11, 20];
var ids2 = [5, 6, 9, 11];
console.log(check_array(ids1, ids2)); // false
console.log(check_array(ids2, ids1)); // false
var search = [1, 6, 9, 11, 20];
console.log(check_array(search, ids2)); // false
console.log(check_array(search, ids1)); // true

Although the generic version above is enough, here's one that's exactly what you ask:

function check_array(ids) {
    var search = [1, 6, 9, 11, 20];
    return $(search).not(ids).get().length === 0;
}
var ids1 = [1, 6, 9, 11, 20];
var ids2 = [5, 6, 9, 11];
console.log(check_array(ids1)); // true
console.log(check_array(ids2)); // false

score 1 · Answer 2 · answered Jun 25 '13 at 12:58

1

If you only have numeric IDs, then this is possibly the simplest way.

[1,2,3].toString() === [1,2,3].toString() //=> true

If you want to determine if all the IDs in array A exist in array B (but array B may have others), try [].every

answered Jun 25 '13 at 12:58

Graham

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arg got me to it... Please add sorting just before comparing :) – Salketer Jun 25 '13 at 12:58
great stuff either of them should work :) – Zabs Jun 25 '13 at 13:00
what if search array has more value than ids? Op wants to return true or false? – A. Wolff Jun 25 '13 at 13:01
@roasted - it depends if that's what the OP wants. If so, they can try `every` as suggested in the edit. – Graham Jun 25 '13 at 13:02
1

@Graham ya, i'm agree with you, we don't know what OP wants as his question is quite incomplete – A. Wolff Jun 25 '13 at 13:03
cheers guys - some good ideas there. – Zabs Jun 25 '13 at 13:05

How to check all items match in an array using javascript/jQuery

2 Answers2