I have an array of products that are stored as Strings in this format productname:quantity. The issue I am running into is that if a user adds one product with a quantity of x it is inserted into the array as it should. However, if they then decide to add more of a particular product a new entry is made into the array instead of checking if the product already exists and adjusting the quantity to the new value. oldQty + newQty. 
For example this is my array:
["CBL202659/A:1","OUTER9:1","PALLET CARDS:1"]
If I add another PALLET CARDS product it creates a new entry rather than updating the quantity of the existing item to 2.
New array
["CBL202659/A:1","OUTER9:1","PALLET CARDS:1","PALLET CARDS:1"]
I would like the array to end up like this: - updating the quantity
["CBL202659/A:1","OUTER9:1","PALLET CARDS:2"]
Currently this is my code:
I use the split() method to seperate the String where a colon occurs and store the product name and quantity in two seperate variables. 
$(".orderBtn").click(function(event){
        //Show the order Box
        $(".order-alert").show();
        event.preventDefault();
        //Create the Array
        var productArray = [];  
        //Get reference to the product clicked
        var stockCode = $(this).closest('li').find('.stock_code').html();       
        //Get reference to the quantity selected
        var quantity = $(this).closest('li').find('.order_amount').val();
        var item = stockCode + ":" + quantity;
        var itemCheck = stockCode + ":";
        if(quantity == 0){
            console.log("Quantity must be greater than 0")
        }else{
            //If no Cookie exists, create one and add the Array
            if ($.cookie('order_cookie') === undefined) {
                console.log("CREATE NEW COOKIE");
                //Add items to Array
                productArray.push(item);
                //Add Array to Cookie
                $.cookie('order_cookie', JSON.stringify(productArray), { expires: 1, path: '/' });
            //If the Cookie already exists do this  
            } else {
                productArray = JSON.parse($.cookie('order_cookie'));//get ref to array
                if(productArray.indexOf(itemCheck)!= -1){//It exists so update qty
                console.log("EXISTS... updating item: " + itemCheck);
                            //var index = productArray.indexOf(item);
                            //var update = productArray[index].split(":");
                            //var name = update[0];
                            //var oldQty = update[1];
                            //console.log(name + ":" + oldQty);
                            //productArray[index] = item;
                }else{//It does not exist, so add to array
                console.log("Does not exist... adding new item: " + item);
                 //Append items onto the Array
                 productArray.push(item);
                }
                //Update the Cookie
                $.cookie('order_cookie', JSON.stringify(productArray), { expires: 1, path: '/' });
                console.log($.cookie('order_cookie'));
            }
            //Display the number of items in the Array in the Order Box
            $('#order_counter').html(productArray.length);
        }
    });
I suppose the real question I am asking here, is if it is possible to search the array for a subString - containing productname: ??