Question

所以一切正常，除了带有＆gt; = largeOrder的if语句，它不会放在折扣中。对于作为承包商的员工也不会。我们必须在那里做出决定，给予每个人最大的折扣，如果员工是承包商，他会得到承包商的折扣。然而，定期承包商if声明是完美的，并且工作正常。所有输出都是正确的。所以我用我的嵌套if语句来猜测它...

//assumptions
var employeeDiscount = .1;
var largeOrder = 800;
var largeOrderDiscount = .05;
var smallOrderDiscount = 0;
var contractorDiscount = .2;
var salesTax = .08;
var seniorTax = 0;
var seniorAge = 90;
var tax, typeOfCustomer, orderAmount, employeeContractor;
var discount, discountAmount, subtotal, finalPrice, taxTotal;


//input

age = prompt("How old is the customer", "");
age = parseInt(age);
orderAmount = prompt("How much is the order", "");
orderAmount = parseInt(orderAmount);
typeOfCustomer = prompt("What type of customer is it, regular, employee, or contractor", "");


//calculations

if (age >= seniorAge) {
    tax = seniorTax;
} else {
    tax = salesTax;
}
if (typeOfCustomer == "regular") {
    if (orderAmount >= largeOrder) {
        discount = largeOrderDiscount;
    } else {
        discount = smallOrderDiscount;
    }
}
if (typeOfCustomer == "employee") {
    employeeContractor = prompt("is the employee a contractor?", "");

    if (employeeContractor == "yes") {
        discount = contractorDiscount;
    } else {
        discount = employeeDiscount;
    }
}
if (typeOfCustomer == "contractor") {
    discount = contractorDiscount;
} else {
    discount = smallOrderDiscount;
}
taxTotal = orderAmount * tax;
discountAmount = orderAmount * discount;
subtotal = orderAmount - discountAmount;
finalPrice = subtotal + taxTotal;

//output

document.write("Order amount: $" + orderAmount);
document.write("<br>Discount amount: $" + discountAmount);
document.write("<br>Subtotal: $" + subtotal);
document.write("<br>Taxes: $" + taxTotal);
document.write("<br>Final Price is: $" + finalPrice);

// -->
</script>

Answer 1

我认为您需要使用if-else-if

修改if block

if (typeOfCustomer == "regular") {
    if (orderAmount >= largeOrder) {
        discount = largeOrderDiscount;
    } else {
        discount = smallOrderDiscount;
    }
} else if (typeOfCustomer == "employee") {
    employeeContractor = prompt("is the employee a contractor?", "");

    if (employeeContractor == "yes") {
        discount = contractorDiscount;
    } else {
        discount = employeeDiscount;
    }
}  else  if (typeOfCustomer == "contractor") {
    discount = contractorDiscount;
} else {
    discount = smallOrderDiscount;
}

根据我的理解，代码中的问题是最后的if-block。

 if (typeOfCustomer == "contractor") {
    discount = contractorDiscount;
} else {
    discount = smallOrderDiscount;  // <== Here previous discount will be overridden if typeOfCustomer is not contractor
}

Answer 2

问题是您每次都使用if而不是else if，这会使您的最后一个if / else语句运行discount = smallOrderDiscount;，除非客户是承包商。这只是一个逻辑错误。

Answer 3

解决此问题的最佳方法是添加关键字

debugger;

就在那些if语句之前。然后按F12（在浏览器中）并重新加载页面，您应该在下次运行在断点处停止的代码时找到，然后您可以使用F12工具逐步查看正在发生的事情。

为什么我的程序没有给我我分配的折扣？

3 个答案: