为什么我的对象没有被推入不同的数组？

Question

I had the objects being pushed from the storeItems array, into the cartItems array and printing in the div successfully, but after adding more functionality it no longer adds to the array (checked via the console and there is a length value of 0). What am I not seeing??

I just need to transfer the user selected object from the storeItems array into the cart Items then it will print successfully

//Function to add an item to users cart & update total
function addItem() {
  var addId = document.getElementById("addItemId").value;
  var itemQty = document.getElementById("addItemQty").value;

  for (x = 0; x < storeItems.length; x++) {
    //Calling validation functions
    validateId();
    validateQty();


    if (addId === storeItems[x].id) {
      cartItems.push(new CartItem(storeItems[x].id, storeItems[x].name, storeItems[x].price, storeItems[x].qty, storeItems[x].shippingCost));
      displayCart();
    }

  }

  console.log(cartItems);
}

I just need to transfer the user selected object from the storeItems array into the cart Items then it will print successfully

Answer 1

Okay, here i go, I did some changes in your code, to make it workable for me.

have a look to my code

var storeItems = [1,2,3,4,5,6]

function addItem(addId, itemQty) {
function addItem(addId, itemQty) {
  for (x = 0; x < storeItems.length; x++) {
    //Calling validation functions
    if (addId === storeItems[x]) {
      cartItems.push(x);
    }
  }
  console.log(cartItems);
}

addItem(6);

According to my deduction, dear Watson, in your code following if condition is not working

 if (addId === storeItems[x].id) {
     ....
    }

debug this condition. this may help you !

Answer 2

Be sure that you are using the correct comparison operator when comparing against a value and a text input. The text input will come back as a string no matter what the type="" value is set to.

So when comparing an input to actual data do one of the following:

• Use == instead of === to ignore/skip type comparisons
• Cast the input value to the type that it should be then you can use ===
  • parseInt(myInput) === myNonInput
  • new Date(myInput).getTime() === myNonInput.getTime()
  • myInput === myNonInput.toString()
  • etc.