Javascript - Get position of the element of the array

Question

For instance, a variable named arrayElements of array type contains [1,2,3,4].

How do i get the position of which that has the value \"3\" in the array variable besi

Answer 1

As was already pointed out by some answers, arrays in newer browsers have methods like indexOf map and forEach that are very convenient for avoiding writing lots of for-loops.

If you need to support old environments without these functions I would strongly recommend using a library (or writing one of your own) to implement those very common array operations (kind of how soc suggested).

var arrayfn = (function(){
    var M = {};

    M.indexOf = function(array, item){ ... };

    M.contains = function(array, item){ return M.indefOf(array, item) !== -1; };

    M.map = function(array, callback){ ... };
}());

arrayfn.contains([1,2,3], 2);

Most popular JS frameworks should already have most of these builtin anyway. Out of the top of my head I remember Dojo, jQuery and Underscore have some of these functions, for example.