Develop Reference

Rewriting JavaScript code with consequent numbers in the names of ids

I'm trying to apply a function to input field with ids that contain consequent numbers (ie. price1, price2, price3), etc.
There's no problem with the first row of field that are defined for a start. But further input fields are dynamically added by a jQuery function and their number is not known in advance.
I hoped it would be an easy loop to apply:
var i=1;
$("#quantity"+i).keyup(function() {
var price= $("#price"+i).val();
var quantity= $(this).val();
var value= price*quantity;
var value=value.toFixed(2); /* rounding the value to two digits after period */
value=value.toString().replace(/\./g, ',') /* converting periods to commas */
$("#value"+i).val(value);
});
So far so good - the outcome of the multiplication properly displays in the id="value1" field after the "quantity" field is filled up.
Now further fields should follow the pattern and calculate the value when the quantity is entered - like this:
[price2] * [quantity2] = [value2]
[price3] * [quantity3] = [value3]
etc.
So the code follows:
$('#add_field').click(function(){ /* do the math after another row of fields is added */
var allfields=$('[id^="quantity"]');
var limit=(allfields.length); /* count all fields where id starts with "quantity" - for the loop */
for (var count = 2; count < limit; count++) { /* starting value is now 2 */
$("#quantity"+count).keyup(function() {
var cena = $("#price"+count).val();
var quantity= $("#quantity"+count).val();
var value= price*quantity;
var value=value.toFixed(2);
value=value.toString().replace(/\./g, ',')
$("#value"+count).val(value);
});
}
});
The problem is that all further "value" fields are only calculated when "quantity2" is (re)entered and the "value2" is not calculated at all.
I guess there's a mistake while addressing fields and/or triggering the calculation.
How should I correct the code?
Just in case the "add_field" function is needed to solve the problem:
$(document).ready(function(){
var i=1;
$('#add_field').click(function(){
i++;
$('#offer').append('<tr id="row'+i+'">
<td><input type="text" name="prod_num[]" id="prod_num'+i+'" placeholder="Product number (6 digits)"></td><td><input type="text" name="prod_name[]" disabled></td>
<td><input type="text" name="cena[]" id="price'+i+'" placeholder="Enter your price"></td>
<td><input type="text" name="quantity[]" id="quantity'+i+'" placeholder="Enter quantity"></td>
<td><input type="text" name="value[]" id="value'+i+'" disabled></td>
<td><button type="button" name="remove_field" id="'+i+'" class="button_remove">X</button></td></tr>');
});

Incrementing IDs is a lot more trouble than it is worth, especially when you start removing rows as well as adding them.
This can all be done using common classes and traversing within the specific row instance.
To account for future rows use event delegation.
Simplified example:
// store a row copy on page load
const $storedRow = $('#myTable tr').first().clone()
// delegate event listener to permanent ancestor
$('#myTable').on('input', '.qty, .price', function(){
const $row = $(this).closest('tr'),
price = $row.find('.price').val(),
qty = $row.find('.qty').val();
$row.find('.total').val(price*qty)
});
$('button').click(function(){
// insert a copy of the stored row
// delegated events will work seamlessly on new rows also
const $newRow = $storedRow.clone();
const prodName = 'Product XYZ';// get real value from user input
$newRow.find('.prod-name').text(prodName)//
$('#myTable').append($newRow)
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<button>Add row</button>
<table id="myTable">
<tr>
<td class="prod-name">Product 1</td>
<td>Qty:<input type="number" class="qty" value="0"></td>
<td>Price:<input type="number" class="price" value="0"></td>
<td>Total:<input type="text" class="total" value="0" readonly></td>
</tr>
<tr>
<td class="prod-name">Product 2</td>
<td>Qty:<input type="number" class="qty" value="0"></td>
<td>Price:<input type="number" class="price" value="0"></td>
<td>Total:<input type="text" class="total" value="0" readonly></td>
</tr>
</table>
Understanding Event Delegation

The first thing to consider is that you can get the length of a selector. So for example:
var count = $("input").length;
If there is one, value here would be 1. if there are four, the value would be 4.
You can also use .each() option to itereate each of the items in the selector.
$('#add_field').click(function(){
var allFields = $('[id^="quantity"]');
allFields.each(function(i, el){
var c = i + 1;
$(el).keyup(function() {
var price = parseFloat($("#price" + c).val());
var quantity = parseInt($(el).val());
var value = price * quantity;
value = value.toFixed(2);
value = value.toString().replace(/\./g, ',');
$("#value" + c).val(value);
});
});
});
You could also create relationship based on the ID itself.
$(function() {
function calcTotal(price, qnty) {
return (parseFloat(price) * parseInt(qnty)).toFixed(2);
}
$('#add_field').click(function() {
var rowClone = $("#row-1").clone(true);
var c = $("tbody tr[id^='row']").length + 1;
rowClone.attr("id", "row-" + c);
$("input:eq(0)", rowClone).val("").attr("id", "prod_num-" + c);
$("input:eq(1)", rowClone).val("").attr("id", "price-" + c);
$("input:eq(2)", rowClone).val("").attr("id", "quantity-" + c);
$("input:eq(3)", rowClone).val("").attr("id", "value-" + c);
$("button", rowClone).attr("id", "remove-" + c);
rowClone.appendTo("table tbody");
});
$("table tbody").on("keyup", "[id^='quantity']", function(e) {
var $self = $(this);
var id = $self.attr("id").substr(-1);
if ($("#price-" + id).val() != "" && $self.val() != "") {
$("#value-" + id).val(calcTotal($("#price-" + id).val(), $self.val()));
}
});
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<button id="add_field">Add Field</button>
<br />
<h2>Product</h2>
<table>
<thead>
<tr>
<td>Number</td>
<td>Name</td>
<td>Price</td>
<td>Quantity</td>
<td>Total</td>
<td></td>
</thead>
<tbody>
<tr id="row-1">
<td><input type="text" name="prod_num[]" id="prod_num-1" placeholder="Product number (6 digits)"></td>
<td><input type="text" name="prod_name[]" disabled></td>
<td><input type="text" name="cena[]" id="price-1" placeholder="Enter your price"></td>
<td><input type="text" name="quantity[]" id="quantity-1" placeholder="Enter quantity"></td>
<td><input type="text" name="value[]" id="value-1" disabled></td>
<td><button type="button" name="remove_field" id="remove-1" class="button_remove">X</button></td>
</tr>
</tbody>
</table>

How to access HTML array object in javascript?

sorry for asking simple question. I am really a beginner in Javascript. I need to access my HTML array form object in my javascript, but I don't know how to do it.
The goal is to trigger the alert in javascript so the browser will display message according to the condition in javascript. Here is my code :
checkScore = function()
{
//I don't know how to access array in HTML Form, so I just pretend it like this :
var student = document.getElementByName('row[i][student]').value;
var math = document.getElementByName('row[i][math]').value;
var physics = document.getElementByName('row[i][physics]').value;
if (parseInt(math) >= 80 ) {
alert(student + " ,You are good at mathematic");
}
if (parseInt(physics) >= 80 ){
alert(student + " ,You are good at physics");
}
student_score.row[i][otherinfo].focus();
student_score.row[i][otherinfo].select();
}
<h2>HTML Forms</h2>
<form name="student_score" action="/action_page.php">
<table border=1>
<thead>
<td>Student</td>
<td>Math Score</td>
<td>Physics Score</td>
<td>Other info</td>
</thead>
<tbody>
<tr>
<td><input type="text" name="row[1][student]"></td>
<td><input type="number" name="row[1][math]" onblur="checkScore()" min="0" max="100"></td>
<td><input type="number" name="row[1][physics]" onblur="checkScore()" min="0" max="100"></td>
<td><input type="text" name="row[1][otherinfo]"></td>
</tr>
<tr>
<td><input type="text" name="row[2][student]"></td>
<td><input type="number" name="row[2][math]" onblur="checkScore()" min="0" max="100"></td>
<td><input type="number" name="row[2][physics]" onblur="checkScore()" min="0" max="100"></td>
<td><input type="text" name="row[2][otherinfo]"></td>
</tr>
<tr>
<td>
<input type="submit" value="Submit">
</td>
</tr>
</tbody>
</table>
</form>
<p>If you click the "Submit" button, it will save the data.</p>

We are going to leverage few things here to streamline this.
The first is Event Listeners, this removes all javascript from your HTML. It also keeps it more dynamic and easier to refactor if the table ends up having rows added to it via javascript.
Next is parentNode, which we use to find the tr that enclosed the element that was clicked;
Then we use querySelectorAll with an attribute selector to get our target fields from the tr above.
/*This does the work*/
function checkScore(event) {
//Get the element that triggered the blur
var element = event.target;
//Get our ancestor row (the parent of the parent);
var row = element.parentNode.parentNode;
//Use an attribute selector to get our infor from the row
var student = row.querySelector("[name*='[student]']").value;
var math = row.querySelector("[name*='[math]']").value;
var physics = row.querySelector("[name*='[physics]']").value;
var otherField = row.querySelector("[name*='[otherinfo]']");
if (parseInt(math, 10) >= 80) {
alert(student + " ,You are good at mathematic");
}
if (parseInt(physics, 10) >= 80) {
alert(student + " ,You are good at physics");
}
otherField.focus();
otherField.select();
}
/*Wire Up the event listener*/
var targetElements = document.querySelectorAll("input[name*='math'], input[name*='physics']");
for (var i = 0; i < targetElements.length; i++) {
targetElements[i].addEventListener("blur", checkScore);
}
<h2>HTML Forms</h2>
<form name="student_score" action="/action_page.php">
<table border=1>
<thead>
<tr>
<td>Student</td>
<td>Math Score</td>
<td>Physics Score</td>
<td>Other info</td>
</tr>
</thead>
<tbody>
<tr>
<td><input type="text" name="row[1][student]" class='student'></td>
<td><input type="number" name="row[1][math]" min="0" max="100"></td>
<td><input type="number" name="row[1][physics]" min="0" max="100"></td>
<td><input type="text" name="row[1][otherinfo]"></td>
</tr>
<tr>
<td><input type="text" name="row1[2][student]"></td>
<td><input type="number" name="row[2][math]" min="0" max="100"></td>
<td><input type="number" name="row[2][physics]" min="0" max="100"></td>
<td><input type="text" name="row[2][otherinfo]"></td>
</tr>
<tr>
<td>
<input type="submit" value="Submit">
</td>
</tr>
</tbody>
</table>
</form>

Well, it follows your line of code exactly as it is (because you said you do not want to change the code too much).
<h2>HTML Forms</h2>
<form name="student_score" action="/action_page.php">
<table border=1>
<thead>
<td>Student</td>
<td>Math Score</td>
<td>Physics Score</td>
<td>Other info</td>
</thead>
<tbody>
<tr>
<td><input type="text" name="row[1][student]"></td>
<td><input type="number" name="row[1][math]" onblur="checkScore(this)" min="0" max="100"></td>
<td><input type="number" name="row[1][physics]" onblur="checkScore(this)" min="0" max="100"></td>
<td><input type="text" name="row[1][otherinfo]"></td>
</tr>
<tr>
<td><input type="text" name="row1[2][student]"></td>
<td><input type="number" name="row[2][math]" onblur="checkScore(this)" min="0" max="100"></td>
<td><input type="number" name="row[2][physics]" onblur="checkScore(this)" min="0" max="100"></td>
<td><input type="text" name="row[2][otherinfo]"></td>
</tr>
<tr>
<td>
<input type="submit" value="Submit">
</td>
</tr>
</tbody>
</table>
</form>
JavaScript [Edited again using part of the #Jon P code, the query selector is realy more dynamic, and the value of the "other" field you requested is commented out]
//pass element to function, in html, only add [this] in parenteses
checkScore = function (element) {
//Get our ancestor row (the parent of the parent);
var row = element.parentNode.parentNode;
//Use an attribute selector to get our infor from the row
var student = row.querySelector("[name*='[student]']").value;
var math = row.querySelector("[name*='[math]']").value;
var physics = row.querySelector("[name*='[physics]']").value;
var other = row.querySelector("[name*='[otherinfo]']");
if (parseInt(math) >= 80) {
//other.value = student + " ,You are good at mathematic";
alert(student + " ,You are good at mathematic");
}
if (parseInt(physics) >= 80) {
//other.value = student + " ,You are good at physics";
alert(student + " ,You are good at physics");
}
otherField.focus();
otherField.select();
}
Tested :), and sorry about my english!

Try that, haven't tested it
var form = document.getElementsByName("student_score")[0];
var students = form.getElementsByTagName("tr");
for(var i = 0; i < students.length; i++){
var student = students[i].childnodes[0].value;
var math = students[i].childnodes[1].value;
var physics = students[i].childnodes[2].value;
if (parseInt(math) >= 80 ) {
alert(student + " ,You are good at mathematic");
}
if (parseInt(physics) >= 80 ){
alert(student + " ,You are good at physics");
}
}

Adding more values from another field with JavaScript

Need help to solve a JavaScript problem.
i am working on an invoice in which i want to add more values to quantity field.
i am trying with script given in JSFiddle.
The problem is when i click on edit , it should popup a dialog box and by entering data in add field it should be added to current quantity of a specific item.
https://jsfiddle.net/programmer/LLmrp94y/16/
JS script
$(document).on('change', '.addQty', function () {
id_arr = $(this).attr('id');
id = id_arr.split("_");
add = $('#add_'+id[1]).val();
qty = $('#quantity_'+id[1]).val();
if (add != '' && typeof (add) != "undefined") {
$('#add_'+id[1]).val();
added = parseFloat(qty) + parseFloat(add);
$('#qtY_'+id[1]).val(added);
priceAfter = $('#price_'+id[1]).val();
$('#Total_'+id[1]).val((parseFloat(priceAfter) * parseFloat(added)).toFixed(2));
} else {
$('#quantity_'+id[1]).val(qty);
$('#Total_'+id[1]).val((parseFloat(price) * parseFloat(qty)).toFixed(2));
}
});

I made it work by doing the following :
adding an id to your edit buttons, so we can retrieve the id of the line currently being edited
replacing your 'onchange' function by a addQuantity function that takes a parameter : the id of the line being edited.
fixing a couple issues with the ids used in the code written to calculate the new quantity and the new price
Also, I replaced your php code by hard coded ids. You're going to have to replace them.
EDIT : Since you don't want to show the current quantity in the dialog, I had to change the logic and update the table after close has been clicked. Otherwise it caused too many issues. Hope you like it.
$(document).ready(function() {
calculateEachItemSubCost();
});
function calculateEachItemSubCost() {
var qtys = document.getElementsByClassName('quantity');
var price = document.getElementsByClassName('price');
var item_costs = document.getElementsByClassName('totalLinePrice');
for (var i = 0; i < item_costs.length; ++i) {
item_costs[i].value = parseFloat(qtys[i].value) * parseFloat(price[i].value).toFixed(2);
}
}
/* new function that replaces your 'onchange' listener. It handles the adding of a quantity on a given line, identified by the id parameter */
function addQuantity(id) {
var add, added, priceAfter;
add = $('#addedQuantity').val();
console.log("Adding " + add + " on line " + id);
if (add != '' && typeof add != "undefined") {
;
added = parseInt($('.add').val()) + parseInt($('#quantity_' + id).val())
$('#quantity_' + id).val(added);
priceAfter = $('#price_' + id).val();
$('#total_' + id).val((parseFloat(priceAfter) * parseFloat(added)).toFixed(2));
} else {
$('#quantity_' + id).val(qty);
$('#Total_' + id).val((parseFloat(price) * parseFloat(qty)).toFixed(2));
}
}
$(document).on('click', '.editnow', function(event) {
var lineId, quantityField;
// retrieving the id of the line that was clicked on
lineId = event.target.id.split("_")[1];
quantityField = $("#quantity_" + lineId);
$(".add").val("");
$("#edit").dialog({
show: "fold",
hide: "fold",
modal: true,
title: "Edit",
zIndex: 10000,
close: function(event, ui) {
addQuantity(lineId);
$(this).hide();
}
});
});
#edit{
display:none;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://code.jquery.com/ui/1.12.0/jquery-ui.min.js"></script>
<link rel="stylesheet" href="https://code.jquery.com/ui/1.12.1/themes/ui-lightness/jquery-ui.css"/>
<!DOCTYPE html>
<!-- Begin page content -->
<h1 class="text-center title">Invoice</h1>
<table>
<thead>
<tr>
<th width="38%">Item Name</th>
<th width="15%">Price</th>
<th width="15%">Quantity</th>
<th width="15%">Total</th>
<th width="15%">Edit</th>
</tr>
</thead>
<tbody>
<tr>
<td><input type="text" value="samsung galaxy s6" id="itemName_1" ></td>
<td><input type="number" value="500" id="price_1" class="price"></td>
<td><input type="number" value="1" id="quantity_1" class="quantity"></td>
<td><input type="number" value="" id="total_1" class="totalLinePrice"></td>
<td><button type="button" class="editnow" id="edit_1"> Edit </button></td>
</tr>
<tr>
<td><input type="text" value="samsung galaxy s7" id="itemName_2" ></td>
<td><input type="number" value="700" id="price_2" class="price"></td>
<td><input type="number" value="1" id="quantity_2" class="quantity"></td>
<td><input type="number" value="" id="total_2" class="totalLinePrice"></td>
<td><button type="button" class="editnow" id="edit_2"> Edit </button></td>
</tr>
</tbody>
</table>
<div id="edit">
<table>
<tr>
<th>Add</th>
</tr>
<tr>
<td><input type="number" class="add" id="addedQuantity"></td>
</tr>
</table>
</div>
Your updated JSFiddle

I have edited it, but it does not work because of the php values not working, of course. I've added id to Edit buttons, and getting value from dialog. Based on the button id, you can enter value to corresponding quantity field
<button type="button" id="edit_<?php $i; ?>" class="editnow"> Edit </button>
Yes: function () {
var id = $(this).attr('id');
id = id.substring(id.indexOf('_')+1);
alert($('#quantityVal').val()); // just check the value
$('#quantity_'+id).val($('#quantityVal').val());
$(this).dialog("close");
},
Edit dialog number field
<td><input type="number" class="add" id="quantityVal"></td>
https://jsfiddle.net/LLmrp94y/12/

Adding to a value declared in another function

It is hard to explain, you can see a DEMO HERE
I have a products table that dynamically creates/deletes new lines of products. I also have a totals table that totals up the totals of each line together.
In that totals box, I have a travel box I want to add to the grand total, but the issue I am having is the travel input is outside the table that is totaling all the values. I can replace the total with a new total, but I can not seem to call the sub total, add the travel and output a grand total.
HTML
<table class="order-details">
<tbody>
<tr>
<td><input type="text" value="" name="" placeholder="Work Description" class="wei-add-field description 1"/></td>
<td><input type="text" value="" name="" placeholder="QTY" class="wei-add-field quantity 1" /></td>
<td><input type="text" value="" name="" placeholder="$0.00" class="wei-add-field unit-price 1"/></td>
<td><input type="text" value="" name="" placeholder="$0.00" class="wei-add-field price-total 1" id=""/></td>
<td> </td>
</tr>
</tbody>
</table>
<div class="wei-add-service">Add Item</div>
<table class="wei-add-totals">
<tr>
<td width="50%">Sub Total</td>
<td width="50%" class="wie-add-subtotal"> </td>
</tr>
<tr class="alternate travel">
<td>Travel</td>
<td><input type="text" value="" placeholder="0.00" class="wei-add-field travel" /></td>
</tr>
<tr>
<td>Taxes</td>
<td><input type="text" value="" placeholder="0.00" class="wei-add-field wie-total-taxes" id="wei-disabled" disabled/> </td>
</tr>
<tr class="alternate total">
<td>Total</td>
<td><input type="text" value="" placeholder="0.00" class="wei-add-field wie-grand-total" id="wei-disabled" disabled/></td>
</tr>
</table>
Javascript
var counter = 1;
var testArray = [ 2,3,4,5];
jQuery('a.wei-add-service-button').click(function(event){
event.preventDefault();
counter++;
var newRow = jQuery('<tr><td><input type="text" class="wei-add-field description ' + counter + '"/></td><td><input type="text" class="wei-add-field quantity ' + counter + '" /></td><td><input type="text" class="wei-add-field unit-price ' + counter + '"/></td><td><input type="text" value="" name="" placeholder="$0.00" class="wei-add-field price-total ' + counter + '" id=""/></td><td>X</td></tr>');
jQuery('table.order-details').append(newRow);
});
jQuery('table.order-details').on('click','tr a',function(e){
e.preventDefault();
var table = $(this).closest('table');
jQuery(this).parents('tr').remove();
reCalculate.call( table );
});
jQuery('table.order-details').on("keyup", "tr", reCalculate);
function reCalculate() {
var grandTotal = 0;
jQuery(this).closest('table').find('tr').each(function() {
var row = jQuery(this);
var value = +jQuery( ".unit-price", row ).val();
var value2 = +jQuery( ".quantity", row ).val();
var total = value * value2;
grandTotal += total;
jQuery( ".wei-add-field.price-total", row ).val( '$' + total.toFixed(2) );
});
jQuery(".wie-add-subtotal").text( '$' + grandTotal.toFixed(2));
}

I don't think, given the task of creating this, I would have chosen to do it in the way you did.
However, using your existing code you can bind the Travel value on change, paste, or keyup and run a function on any of those actions. Within that function I have removed the special character ($) from ".wie-grand-total" using a regex and converted the value of ".wie-grand-total" to a float using parseFloat. I also converted the Travel value to a float using parseFloat. I then added them together and made the sum your new value for "wie-grand-total".
/* NEW SINCE COMMENTS */
//Add to your HTML New table
<table class="order-details">
<tbody>
<tr>
<td><input type="text" value="" name="" placeholder="Work Description" class="wei-add-field description 1"/></td>
<td><input type="text" value="" name="" placeholder="QTY" class="wei-add-field quantity 1" /></td>
<td><input type="text" value="" name="" placeholder="$0.00" class="wei-add-field unit-price 1"/></td>
<td><input type="text" value="" name="" placeholder="$0.00" class="wei-add-field price-total 1" id=""/></td>
/* NEW SINCE COMMENTS*/
<td><input type="text" id="travelHid" value=""></td>
<td> </td>
</tr>
</tbody>
</table>
/* NEW SINCE COMMENTS */
$('#travelHid').hide();
var travelVal = 0;
function updateTravelVal(travelVal){
var travelVal = travelVal;
$('#travelHid').val(travelVal);
};
updateTravelVal();
$("#travelVis").bind("change paste keyup", function() {
var noChars = jQuery(".wie-grand-total").val().replace(/[^0-9.]/g, "");
var newTot = parseFloat(noChars) + parseFloat($(this).val());
jQuery(".wie-grand-total").val( '$' + newTot.toFixed(2));
//added error checking
var checkError = jQuery(".wie-grand-total").val( '$' + newTot.toFixed(2));
//if the value that would go in input is NaN then use travelVal
//since there is no value in .wie-grand-total yet
if (typeof checkError !== "string") {
jQuery(".wie-grand-total").val( '$' + travelVal.toFixed(2))
} else if (typeof checkError === "string") {
jQuery(".wie-grand-total").val( '$' + newTot.toFixed(2))
}
/* NEW SINCE COMMENTS */
updateTravelVal(travelVal);
});
A fiddle for demonstration (now with hiddenVal per comment)
http://jsfiddle.net/chrislewispac/wed6eog0/3/
Only potential problems here are it only runs when you change, paste, or key up the value in #TravelVis.
/EXPLAINED SINCE COMMENTS/
It the html I added a td with input. Input id="travelHid". I then make that invisible by applying jQuery method .hide(). I then exposed travelVal to global scope an initiated it with a value of zero then created a function to update that value.
Within that function I set the value to the argument travelVal or to 0 if there are no args. I then immediately call it.
Then, I added a call to that function with the arg travelVal from our bind function to update it if a value is present.
And finally:
Just add a row to the table with preset value of Travel and Quant 1.
http://jsfiddle.net/chrislewispac/xntn7p5p/5/

Using jQuery to validate value in comparison to other input value

So I have a base Hour input field and I'm trying to validate the other input fields so that once the base hour is added the other input values can only be as large as the first base rate Hours column (first input). Or put another way the one input field becomes the max number value once it is entered. So if the base is 12 for the Hours column the second and third rate can be no larger than 12. The tricky part is add new row feature means all new rows for the hour column have to adhere to the rule as well. I have been trying to figure it out for a bit, any help would be appreciated.
Here is the fiddle: http://jsfiddle.net/uuzhuom9/
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script>
<script>
$(document).ready(function () {
$('#calculate').on('click', function() {
$('.hours-table tr').each(function() {
var hours = $(this).find('input.hours').val();
var rate = $(this).find('input.rate').val();
var dateTotal = (hours * rate);
$(this).find('input.date-total').val(dateTotal);
// total += parseInt($("input.date-total").val());
var sum = 0;
//iterate through each textboxes and add the values
$("input.date-total").each(function () {
//add only if the value is number
if (!isNaN($(this).val()) && $(this).val().length != 0) {
sum += parseFloat(this.value);
}
});
if (sum < 0) {
alert("Total can't be negative");
$('#grandtotal-new').val('');
} else {
$("#grandtotal-new").val(sum)
}
}); //END .each
return false;
}); // END click
});
$(function(){
var counter = 4;
$('a.add-row').click(function(event){
event.preventDefault();
counter++;
var newRow = jQuery('<tr><td><input type="text" value="" /></td><td><input type="text" class="hours" name="rate-0' + counter + '"/></td><td><input type="text" class="rate" name="rate-0' + counter + '"/></td><td><input type="text" class="date-total" readonly name="date-total-0' + counter + '"/></td></tr>');
$('table.hours-table').append(newRow);
});
});
</script>
The html is:
<table class="hours-table">
<tr>
<th>Item</th>
<th>Hours</th>
<th>Hourly Rate</th>
<th>Total</th>
</tr>
<tr>
<td>Base Rate:</td>
<td class="hours"><input type="number" class="hours" id="base-hours" name="hours-01" max="???" min="???" value="" /></td>
<td class="rate"><input min="0" class="rate" name="rate-01" value="200" readonly /></td>
<td class="date-total"><input type="text" class="date-total" name="date-total-0" readonly /></td>
</tr>
<tr>
<td>Second Rate:</td>
<td class="hours"><input type="number" class="hours" name="hours-02" max="???" min="???" value="" /></td>
<td class="rate"><input type="text" class="rate" name="rate-02" value="-20" readonly /></td>
<td class="date-total"><input type="text" class="date-total" name="date-total-1" readonly /></td>
</tr>
<tr>
<td>Third Rate:</td>
<td class="hours"><input type="number" class="hours" name="hours-03" max="???" min="???" value="" /></td>
<td class="rate"><input type="text" class="rate" name="rate-03" value="10" readonly /></td>
<td class="date-total"><input type="text" class="date-total" name="date-total-2" readonly/></td>
</tr>
</table>
Add New Rule<br />
<button type="button" id='calculate' class="btn btn-inverse btn- mini">Calculate</button>
The Grand total is: <input type="number" id='grandtotal-new' min="???"/>

Just validate them on blur of each .hours input as below:
DEMO
$(document).on('blur','.hours',function(){
var current=$(this);
if(!(current).is('input.hours:first'))
{
if(current.val()>$('input.hours:first').val())
current.val('');
}
});
This will check value of input on blur and clears it if it is greater than first one
UPDATE:
DEMO
parse the value before checking as below:
$(document).on('blur','.hours',function(){
var current=$(this);
if(!(current).is('input.hours:first'))
{
if(parseInt(current.val())>parseInt($('input.hours:first').val()))
current.val('');
}
});
UPDATE 2
Based on OPs comments here is the way to achieve the requirements mentioned by him.
DEMO
$(document).on('blur','.hours',function(e){
var current=$(this);
var base=$('input.hours:first');
var total=0;
var other=$('input.hours:not(:first)');
if(base.val()==="")
{
alert('Enter Base First');
current.val('');
base.focus();
e.stopPropagation();
return;
}
$.each($(other),function(index,value){
if(value.value!=="")
total+=parseInt(parseInt(value.value));
});
console.log(total);
if(!(current).is(base))
{
if(parseInt(current.val())>parseInt(base.val()))
{
current.val('');
}
else if(total>parseInt($('input.hours:first').val()))
current.val('');
}
});

add this at the beginning of your jquery script.
this will limit the other hours input to whatever is on base-hours, including newly added rows.
var baseRate = 0;
$(".hours-table").on("input","input.hours",function() {
if ($(this).attr('id') == 'base-hours'){
baseRate = $(this).val();
}else if ($(this).val() > baseRate){
$(this).val(baseRate);
}
});
and then further down below you have a syntax/logic error on your add row function. replace this line with this corrected line, and you might wanna move your counter++ after this line.
var newRow = jQuery('<tr><td><input type="text" value="" /></td><td><input type="text" class="hours" name="rate-0' + counter + '"/></td><td><input type="text" class="rate" name="rate-0' + counter + '"/></td><td><input type="text" class="date-total" readonly name="date-total-0' + counter + '"/></td></tr>');
check this jsfiddle - http://jsfiddle.net/uuzhuom9/8/