We Keep Coding

How to accumulate a score/value based on the choices selected on a form using jQuery

I wanna to try to researching around on how to achieve this but I am not sure about how to make the solution for this.
Basically I have a form that contains some select list, radio buttons, and checkboxes. Each option on the form has a corresponding numeric value that will be accumulated and displayed to the user when the form gets submitted.
What I am not sure about is how to be able to add or deduct a value if the user chooses to change the a choice on the form.
For example, when a user is on the first dropdown element, and they choose option 2 which has a value of 5 then the current accummulated value us 5. Then on question 2, they choose option 1 which has a value of 2 which makes the accummulated value 7. Then the user changes the answer for question one from option 2 to option one which means 5 will be deducted from the accumulated value and 2 will be added since it is the value for option 1 which changes the accumulated value to 4.
I know the description I mentioned might be all over the place but I hope it makes sense.
I am trying to use jQuery and so far, my approach would be to check if any of the form element's value has changed:
(function($) {
var score = 0;
$(".the-form #step-5 :input").change(function() {
console.log($(this).val());
});
})(jQuery);
But I can't seem to figure out how to get the previous value of the option that was selected if the user changes their answer.
Any suggestion would be appreciated.

Can you recalculate across the whole form each time the user changes any of the elements?
$(".the-form :input").change(calculateChanges);
function calculateChanges() {
// Retrieve the current values of all elements and add them together
}

When a user submits, then start doing the calculations or when a select is changed, i.e. attach it to the event. Score is now a local variable
function calcValue() {
var score = 0;
//select all the elements using example below
$(".the-form :input").each(function( index ) {
//i forgot jQuery exact syntax but $(this).val or //$(this).val()
score += $( this ).val();
});
console.log(score);
}
In this case you can attach it to the submit
function submit() {
var score = calcValue();
}
Or you can put it in a change event of a select
function selectChanged() {
var score = calcValue();
}

Jquery in loop to perform some calculation of records

Iam trying to bring some records using php and do some calculations. What iam doing now is that, each rows is having a dropdown with different currencies. When i select each currency, it calculates and shows certain values. Till here its working fine.
What i am trying to achieve is that if i select first currency dropdown, it should calculate the complete records calculations instead of selecting the currency of each rows. I guess i need to do some kind of loop in the jquery which calculates the rows.
Fiddle
Following is the part of jquery script for the currency dropdown.
$(window).load(function() {
$(document).ready(function() {
$("select").on('change', function() {
var dept_number = $(this).val();
var price = $(this).find(':selected').data('price');
var selected = $(this).find('option:selected').text();
if (selected == "INR") {
$(this).closest('table').find('.total1').val($(this).closest('table').find('.total').val());
} else {
$(this).closest('table').find('.total1').val((($(this).closest('table').find('.total').val() * price) / $(this).closest('table').find('.inrvalue').val()).toFixed(3));
}
$(this).closest('table').find('.price_unit').val(($(this).closest('table').find('.total1').val() / $(this).closest('table').find('.qty').val()).toFixed(3));
});
});
});
i guess i need to add some loops here in this jquery. Anyone to guide me how to do this. Or i need to follow a different step.
This is what i have tried as per the suggestion from Leonix.
$(document).ready(function(){
$(this).closest('table').find("select").each(function() {
var dept_number = $(this).val();
var price = $(this).find(':selected').data('price');
var selected = $(this).find("select");
if(selected=="INR")
{
$(this).closest('table').find('.total1').val($(this).closest('table').find('.total').val());
} else
{
$(this).closest('table').find('.total1').val((($(this).closest('table').find('.total').val() * price) / $(this).closest('table').find('.inrvalue').val()).toFixed(3));
}
$(this).closest('table').find('.price_unit').val(($(this).closest('table').find('.total1').val()/$(this).closest('table').find('.qty').val()).toFixed(3));
});
});

In your select change function, do a each for all rows of your table and find the dropdown:
$(this).closest('table').find("select").each(function() {
/* Each SELECT here, use $(this) */
})
or, depending of your needs :
$(this).closest('table').find("select").each(function() {
/* Each TR here, use selectInput */
var selectInput = $(this).find("select");
})
With the select in hands, use selectInput.val(changedSelectInput.val())
changedSelectInput is the jquery object containing the select who changed.
Using nested anonymous functions, take care, they are executed in the object context, so this and $(this) change depending on the object affected by function.
Advice: Use specific css classes for JS, as select.select-currency instead of select only, put these classes in your code. it will prevent so many mistakes and will save your time.
Note: currency_change[] is not a valid ID, if you dont need to set one, dont.
EDIT
Some code: https://jsfiddle.net/btpxq5ow/6/
What I did ?
Fix tags issues
Fix input in tbody issues, NEVER put it in a tr, tbody, table directly.
Fix some indentation issues
Apply the currency change to all rows
Prevent change event to call itself in an infinite loop
Apply calculation to all rows when they are updated
Fix some code syntax & performance issues
Please check your calculation are right since i modified it, see calculateRowTotals().
There are still a few html/js errorsthat must be fixed.
You will rarely get code from stackoverflow

Discount calculation of dynamic input box using javascript

I am trying to calculate discounted price which I am able to do without anyproblem for a single item. I also have 'add more' button to add many item as I can. So here, I started facing problem in calculating the discounted price for these dynamically added input field.
My default discount calculation script for single item is
$('#discount_1').change(function(){
var quantity=$('#qty_1').val();
var percent=$('#discount_1').val();
var price=$('#price_1').val();
var tprice = price * quantity
var discountpercent=percent / 100;
var discountprice=(tprice * discountpercent );
$('#total_1').val(tprice - discountprice);
});
I tried changing it to the following
$(":input[id^='discount_']").change(function(){
var quantity=$(":input[id^='qty_']").val();
var percent=$(":input[id^='discount_']").val();
var price=$(":input[id^='price_']").val();
var tprice = price * quantity
var discountpercent=percent / 100;
var discountprice=(tprice * discountpercent );
$(":input[id^='total_']").val(tprice - discountprice);
});
to calculate discount for all the item set having id attribute that starts with qty_, which actually does not seem to work properly.
here is my jsFiddle

I've modified this to remove all ids. This will clean up a lot of extra crap. Here is a fiddle: http://jsfiddle.net/B5T6R/1/
The solution involved event delegation. The problem with $(":input[id^='discount_']").on('change' is that the future trs don't exist yet, so there is nothing to bind to!
The solution is:
$("#InputsWrapper").on('change', '.discount'
Which will listen for all future changes on the InputsWrapper table as a whole, not just to the discount elements.

The problem is that the selectors you are using will always select the first input that matches the selector.
So, (":input[id^='qty_']") will always match the input on the first row.
I suggest:
Rebind the "change" event evertime AddButton is clicked. This will
require .unbind() as well.
Add class "discount" to all discount inputs.
Change the selectors for quantity, price, etc to be relative to the input that was changed.
IE:
$('.discount').unbind().change(function(){
var $parentRow = $(this).parent().parent();
var quantity=$(":input[id^='qty_']", $parentRow).val();
});

It's not a great idea to use all these id's: #qty_1, #qty_2, etc. Instead give all your inputs the same class names to hook into, for example:
<input class='discount' type='text' name='discount'/>
<input class='quantity' type='text' name='quantity'/>
Then use good ole Jquery to traverse the DOM and fetch the relevant data. In this case you have to climb to the closest td and then back down to get the .quantity class, as so:
$(".discount").change(function(){
var quantity = $(this).closest('td').find('.quantity').val();
});
Hope this helps.

You are running into a couple of problems.
First, only the ":input[id^='discount_']" that exist on your page when the DOM is initialized have this change handler added to them - all new rows added via the the Add More Field link will not have this handler bound. You can get around this by attaching the handler to the container all of your fields are in via .on, so that every change event fired within that container will be checked against the selector specified. I've forked your fiddle to demonstrate: http://jsfiddle.net/gLz9B/1/
$('#InputsWrapper').on("change", ":input[id^='discount_']", function(){
...
});
The second issue is that the qty_, total_, price_, and discount_ selectors you are using will return arrays, rather than being limited to the specific row where the change is occurring. In my fiddle fork I did a string replace to get the unique number attached to the id of the element, and then build the ids of all of the other inputs rather than using =^ to select them. This is not the only way to limit your scope, but it works given your sample code.
var id = this.id.replace('discount_','');
var quantity=$("#qty_" + id).val();

jQuery increase / decrease value on input checked

I'm working on this eCommerce project where I need to calculate "shipping costs" if a particular checkbox is checked.
Here's the code for the checkbox :-
<div class="alert alert-info">
<p>Shipping Outside Lagos (N2, 000)</p>
<input type="checkbox" name="shipping" id="shipping">
</div>
How can I write the jQuery function, so that when the input is checked..I can get the value in a variable. Suppose the default value is 2000, how would I be able to get $amount=2000 (if checked) and $amount remains 0 if unchecked.
Due to my limited knowledge in jQuery / JavaScript, I'm unable to find a solution for it.
Search didn't help either.
Any suggestions are welcome.

var amount = $('#shipping').is(':checked') ? 2000 : 0;
$('#shipping').on('change', function() {
amount = this.checked ? 2000 : 0;
});
// use amount

You can do:
var shippingAmt = 0;
$("#shipping").change(function() {
shippingAmt = this.checked ? 2000 : 0;
});

I'd suggest using a function to determine the cost of items. You could have an abstract of determining costs which would run through a few or several conditions to calculate 'add ons' so to speak.
So you'd have your initial total of say $500.99, then run that value through something like calculateTotalValue(value)
It would check if any add-ons were checked in the form, and add their values to the initial value.
This would allow you to have any number of extras, like shipping, or even add-ons/upgrades for the product itself, and you'd be able to fetch the total without fail in each case. You could have a generic way of stipulating that a field is an 'add on' so you wouldn't need to maintain a list, like so:
<input type="checkbox" rel="add-on" data-add-on-type="shipping" value="500">
Then in your function,
calculateTotalValue(value) {
$.each($('input[rel="add-on"]'), function(i) {
// You probably want some error checking here
value += this.val();
});
return value;
}
If necessary you could use data-add-on-type to keep track of where costs comes from to output a list for the user, as well.

jQuery: Total values in textboxes automatically

I have a series of textboxes with the following IDs:
118|1/9/2011
118|1/10/2011
118|1/11/2011
118|1/12/2011
118|1/13/2011
118|1/14/2011
118|1/15/2011
118|Total
Using jQuery or just javascript, I need to sum each textbox and assign the value to the total textbox. This needs to happen when a user tabs off or clicks off the textbox. It also needs to be generic enough to handle textboxes with similar IDs such as:
119|1/9/2011
119|1/10/2011
119|1/11/2011
119|1/12/2011
119|1/13/2011
119|1/14/2011
119|1/15/2011
119|Total
The format stays the same. Only the first numbers to the left of the | will change.
Any guidance would be greatly appreciated.

EDIT: I updated my answer to reflect the actual example HTML that Mike provided, which you can view in this fiddle. That link also contains the working javascript from below.
If you have a specific selector for the inputs you want to sum (like a class name), as well as one for the total, you should be able to do this (here's a fiddle link with this javascript in action: http://jsfiddle.net/avidal/zfjmD/):
$('input.sum').change(function() {
var sum = 0;
// we want to sum up the values of all input.sum elements that are in the same tr
// as this one
$(this).closest('tr').find('input.sum').each(function(i) {
var val = parseInt($(this).val(), 10);
/*
change the above line to:
var val = parseFloat($(this).val());
if the inputs will be floats
*/
if (isNaN(val) || val === undefined) {
return;
}
sum += val;
});
$(this).closest('tr').find('input.total').val(sum);
});
The important things to note are the .closest() function, and the .find() function.
First, we bind to the change event for all inputs with a class of sum. When one of those elements is changed (the value changes, then the user clicks/tabs out), we look for the closest tr element, then find the list of inputs with a class of sum that are children of that tr. For each of those inputs, we parse the value and accumulate the sum. After we've iterated over each of those inputs, we finally find the input with a class of total that's a descendant of the closest tr, and set the val of that input to the accumulated sum
Perfect!

Great question and great answer! This works perfectly! To answer Mike, I changed 'tr' to 'table' in the jQuery and it totals all the sums in a table across several tr's and td's. As long as the inputs have the class="sum" they will be totaled.