CODEWITHSUNDEEP
javascriptarraysforms
user1361276
user1361276

Reputation: 99

Calculating the total of an order: Applying discounts

I'm working on an online orderform using javascript. I almost have it working, but what I would like to do is apply a 12.5% discount if more than 5 items are selected. So far I have managed to get the discount to apply if more than any one item is selected. Here is my code: 

var totalItems = 0

// Run through the form fields to check for any filled fields
for (var i=0; i<juiceForm.length; i++)
{

    n=0;
    juicetotal = 0;
    itemQuantity = Number(parseInt(juiceForm[i].value)); // convert field value to a number

    itemQuantity = parseInt(juiceForm[i].value);
    if (isNaN(itemQuantity)) 
    {
        itemQuantity = 0; // If the form field value is not a number, make it zero
    }

    // count the total number of juices selected
    totalItems = totalItems += Number(parseInt(juiceForm[i].value));

    if (totalItems >= 5 || itemQuantity >= 5 || (totalItems + itemQuantity) >= 5)
    {
        juiceTotal = (juiceTotal+(itemQuantity * juicePrice[i]))*0.875;
    }
    else 
    {
    // Multiply the quantity by the item price and update the order total   
        juiceTotal = juiceTotal+(itemQuantity * juicePrice[i]);
    }
}

Where I'm running into trouble is if multiple items are selected giving a total of more than 5 items, the calculation is coming out wrong. For example, if I have 5 crates of apple juice at £20 and 1 crate of orange at £22, with a 12.5% discount I should be getting a total of £106.75 but I am getting £95.81.

I'm not sure if I have made an obvious mistake. Can anyone give me any advice on what I'm doing wrong?

Upvotes: 0

Views: 1097

Answers (1)

Michael Besteck
Michael Besteck

Reputation: 2423

Maybe you think of this (not tested, take it as pseudocode)

var totalItems = 0
var juiceTotal = 0;
for (var i=0; i<juiceForm.length; i++)
{
    var itemQuantity = parseInt(juiceForm[i].value);
    if (isNaN(itemQuantity)) 
    {
        itemQuantity = 0;
    }
    totalItems += itemQuantity;
    juiceTotal += (juicePrice[i]*itemQuantity);  
}

if (totalItems >= 5)
    juiceTotal *= 0.875;
}

Upvotes: 1

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