When you add product with the same Product Id it must increase its quantity and not be able to add a new row. I've tried the comments. Please check it below the js script. But it is still not working.
let Cart = [];
function viewCart() {
let tr = document.createElement('tr');
for (cart of Cart) {
tr.innerHTML = `<td>${ cart.id }</td>
<td>${ cart.desc }</td>
<td>${ cart.qty }</td>
<td>${ cart.price }</td>
<td>${ cart.qty * cart.price }</td>`;
}
cartsTable.appendChild(tr);
}
function AddtoCart(productid, description, quantity, price) {
let inputs = {
id: productid,
desc: description,
qty: quantity,
price: price
};
Cart.push(inputs);
viewCart()
}<script src="script.js"></script>
<input type="button" value="Laptop" onclick="AddtoCart('132','Macbook Pro', 1, 100000)" />
<input type="button" value="Phone" onclick="AddtoCart('456','Iphone 5S', 2, 20000)" />
<input type="button" value="Camera" onclick="AddtoCart('789','Nikon 3D00', 1, 40000)" />
<table border="1|1" id="cartsTable">
<tr>
<th>Product ID</th>
<th>Product Description</th>
<th>Quantity</th>
<th>Price</th>
<th>Total</th>
</tr>
</table>