Check an array contains an item with jQuery

3 October 2014

Check if an array contains an item by using jQuery's inArray:

var a = [1, 2];
$.inArray(a, 2); => 1 // returns the index
$.inArray(a, 3); => -1 // when not found

Use the indexOf of underscore:

_.indexOf(2, a); => 1
_.indexOf(3, a); => -1

If you're not supporting older IE browsers (pre IE9), you can use the native indexOf:

a.indexOf(2); => 1
a.indexOf(3); => -1