Swift - Why is my application finding nil in this scenario - swift

Question

I have an tableView which loads cells from a xib file. The cells contain 2 labels, 1 shows the quantity and the second shows the price. The quantity is pulled from a static model and works just fine, and the price is pulled from a model which is populated from the result of a URLSession. Below is my cellForRowAt function which works fine in this scenario:
if indexPath.section == 0 {
let item: BasketModel = cellItems[indexPath.row] as! BasketModel
let ordersCell = Bundle.main.loadNibNamed("OrderTableViewCell", owner: self, options: nil)?.first as! OrderTableViewCell
ordersCell.priceLabel.text = item.price
ordersCell.quantityLabel.text = String(basketStruct.getQty(id: item.id!))
return ordersCell
}
My cell shows as follows Qty: 3 Price: 0.70
Now, the problem I have is, when i alter the line above where I set the price label to the following:
ordersCell.priceLabel.text = String(basketStruct.getQty(id: item.id!) * Int(item.price!)!)
I get the error:
Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value
What I want, is the qty to be multiplied by the price. However, when I try to use item.price for anything I have to force unwrap it and then I get my error.
How would I go about this ?

Answer 1

It is not that item.price is nil, but Int(item.price!) is nil.
From your question, you said that the price displayed is 0.70, so I suppose item.price must contain the string "0.70".
Well, 0.70 is not a valid Int, so when you try to parse it as an Int, it evaluates to nil.
I think you meant Double(item.price!)!.
As a good practise, you should always check for invalid number strings:
if let price = Double(item.price!) {
// ...
} else {
print("Invalid price: \(item.price!)")
}