Stringify a multi-dimension array with javascript

Question

Im creating an invoice for books, and aim to submit it via ajax. Im trying to json encode the array of books in the invoice, however I keep getting a blank value

 //create item list
    var order_items = [];
    $('#mi_books tbody tr.userbooks').each(function(index)
    {
        var bookisbn = $(this).find('td .mi_isbn').text();

        var bookdata = [];
        bookdata['isbn'] = bookisbn;
        bookdata['title'] = $(this).find('.mi_title').text();
        bookdata['qty'] = $(this).find('.mi_qty').text();
        bookdata['price'] = $(this).find('.mi_price').text();

        order_items.push(bookdata);

    });
    alert(JSON.stringify(order_items));
    alert(order_items.toString());
    console.log(order_items);

alert(JSON.stringify(order_items));
Outputs: [[]]

alert(order_items.toString());
Outputs: blank

console.log(order_items);
Output:

Array[1]
0: Array[0]
isbn: "9781401216672"
length: 0
price: "1007"
qty: "1"
title: "Batman: The Killing Joke"
__proto__: Array[0]
length: 1
__proto__: Array[0]

My array is being created, but somehow I cant seem to json encode it? Am I doing something wrong?

Answer 1

you may try

var order_items = {};
$('#mi_books tbody tr.userbooks').each(function(index)
{
    var bookisbn = $(this).find('td .mi_isbn').text();

    var bookdata = {
      'isbn': bookisbn,
      'title': $(this).find('.mi_title').text(),
      'qty': $(this).find('.mi_qty').text(),
      'price': $(this).find('.mi_price').text()
    };
    order_items[index] = bookdata;
});
alert(JSON.stringify(order_items));

your only mistake was a try to create associative arrays instead of using objects, that can do it

Answer 2

Array and Object are different beasts. Your bookdata is not an array, but an object, thus, you should create it with

var bookdata = {};

Answer 3

Arrays are serialized differently with JSON.stringify() as opposed to regular objects (only properties of UInt32 are serialized). Since you're only adding textual properties to the bookdata, you should use anonymous objects like this:

var bookdata = {
    isbn: bookisbn,
    title: $(this).find('.mi_title').text(),
    qty: $(this).find('.mi_qty').text(),
    price: $(this).find('.mi_price').text()
};