Question

Here’s my code:

var array = [{"number":"500","title":"whatever 500"},{"number":"400","title":"whatever 400"}];

alert(array[0].number); //should output 500

$.each(array, function(index, val)
{
    array[index].number = val * 5;
});

alert(array[0].number); //should output 2500

I’m trying to multiply all the numbers in my array by 5. But for some reason it’s not working. It outputs NaN (Not-a-Number). And when I try to add 50, it outputs [object Object]50.

Can someone please tell me what I’m doing wrong here?

Answer 1

The problem is that val is the object, not a specific value from it. So you’re trying to multiply {"number":"500","title":"whatever 500"} by 5, which unsurprisingly doesn’t work.

You can just use this to refer to the current element in the loop. Your code might look like this:

$.each(array, function() {
    this.number = this.number * 5;
});

You could, in fact, make this even shorter, by using the *= assignment operator:

$.each(array, function() {
    this.number *= 5;
});