Question

var arr = $(".producttypeid");
var premiumtypecodes = Array(arr.length);
for (var i = 0; i < arr.length; i++)
    premiumtypecodes[i] = arr[i].value;

The above code does not seem to work. The intent is to assign the output to an array. Anything that I am missing.
Why this simple code does not work? Reasoning would be highly appreciated….

Based on the feedback I am adding sample markup and adding details to make my intent unambigous.

<input class="producttypeid" type="hidden" value="512">

I want to extract the value from all tags using style producttypeid and make an array

Answer 1

Here’s how I’d do it:

var arr = $(".producttypeid");
var premiumtypecodes = [];
arr.each(function(index) {
    premiumtypecodes[index] = this.value;
});

That assumes all of the matching elements are input elements (because of the use of value). If some of them may be textarea or select elements, then change the line inside the iterator function to:

    premiumtypecodes[index] = $(this).val();

If they’re not form fields at all, you’ll have to define what you mean by their “value” (e.g., you might use $(this).text() to get their text content, or $(this).html() to get their markup, or something else entirely).

I’m not immediately seeing any problem with your version other than that you’re missing an i after var:

for (var = 0; i < arr.length; i++)
//       ^--- here

Other than that, it should have worked, but note that although Array(arr.length) works, the usual way to write it is new Array(arr.length) (and there’s no need to pre-set the length; JavaScript arrays aren’t really arrays so you don’t get the usual benefit of doing that).