javscript smart array loop, need some help here

Question

    var _test1 = [];
    _test1[88] = 'sex';
    _test1[1999990] = 'hey';
    for(i = 0, length = _test1.length; i < length; i++){
        if(_test1[i] == 'hey'){
            alert(_test1.length);
        }
    }

this takes a lot of time, and there are only 2 values. Is there any way to be faster?

Or to use another system that index objects by a number and then loop them fast? thanks

Answer 1

You can use a for / in loop:

for (var i in _test1) {
    if (!_test1.hasOwnProperty(i) || isNaN(+i)) continue;

    if(_test1[i] == 'hey'){
        alert(_test1.length);
    }
}

This is exactly what you're looking for; it will only loop over the indices that are actually defined, and will skip any holes in the array.

Answer 2

Have you tried using an Object instead? Numbers should be converted to strings automatically. You would traverse the list with a for...in loop.