Bleep Bleep! "Your bill is NaN"


#1



https://www.codecademy.com/en/courses/close-the-super-makert/0/5?curriculum_id=506324b3a7dffd00020bf661#


Hello,

I've checked my code with 4 examples and I still can't work it out.

The error message comes up false and the console comes up with "Your bill is NaN".

Please help.


var cashRegister = {
    total:0,
    //Dont forget to add your property
    add: function(itemCost) {
        this.total += itemCost;
        this.lastTransactionAmount = itemCost;
    },
    
    scan: function(item,quantity) {
        switch (item) {
        case "eggs": this.add(0.98 * quantity); break;
        case "milk": this.add(1.23 * quantity); break;
        case "magazine": this.add(4.99 * quantity); break;
        case "chocolate": this.add(0.45 * quantity); break;
        }
        return true;
    },
    //Add the voidLastTransaction Method here
 voidLastTransaction: function(lastTransactionAmount) {
        this.total -= lastTransactionAmount;
 }
    
};

cashRegister.scan('eggs',1);
cashRegister.scan('milk',1);
cashRegister.scan('magazine',1);
cashRegister.scan('chocolate',4);

//Void the last transaction and then add 3 instead
cashRegister.voidLastTransaction();
cashRegister.scan('chocolate',3);

//Show the total bill
console.log('Your bill is '+cashRegister.total);

Continuing the discussion from Bleep Bleep! Oops, try again. false:


#2

HI inside that method

voidLastTransaction: function(lastTransactionAmount) {
        this.total -= lastTransactionAmount;
 }

you should this to lastTransactionAmount


#3

Thank you wizmarco. @_@