JavaScript - Remove element from array (optionally preserve keys)

JavaScript - Remove element from array (unset array element)

1) Method 1: splice
array.splice(position, number_of_keys);
Example:

array.splice(1, 1);

OBS: The function doesn't preserve key association.

2) Method 2:
To preserve key association, you must do something like this:

var my_array = [1, 4, 5, 6];
var remove_key = 1;
var array_new = [];
for(var i in my_array) {
    if(i != remove_key) {
        array_new[i] = my_array[i];
    }
}