Develop Reference

Why is my checkbox on change not working (AJAX)

This is how my razor code looks like
<form asp-action="Save" asp-controller="ClassesHeld" method="post">
<input asp-for="ClassHeldId" value="#Model.ClassHeldId" hidden />
<div class="form-group">
<label>Student</label>
<input asp-for="#Model.Student" value="#Model.Student" class="form-control" readonly />
</div>
<div class="form-group">
<label>Grade</label>
<input id="Grade"asp-for="Grade" type="number" value="#Model.Grade" class="form-control" min="0" max="5" />
</div>
<div class="form-group">
<label>Attendance</label>
<input id="Attendance" class="form-check-input" asp-for="Attendance" type="checkbox"/>
</div>
<button class="btn btn-primary" type="submit" value="Save">Save</button>
</form>
<script>
$("#Attendance").on("change", function () {
$("#Grade").attr("disabled", this.checked);
});
</script>
Yet for some reason, clicking on the checkbox does nothing at all. I have tried this with simple script as well, and that didn't work either.
document.getElementById('Attendance').onchange = function () {
document.getElementById('Grade').disabled = this.checked;
};
Neither of these worked.
I have even copied some solutions from here (one of them is that last simple scrip with document.getElementbyId, and none of it worked. I have to be missing something simple, but I've been looking at this for the past hour and I still can't figure it out.
I apologize if the question is stupid or noob-level. But I am getting desperate.
EDIT: Simply to add more information, this form works perfectly fine when submitting data, controller saves the stuff to the database... Everything works fine, just not the part where it disables the ability to edit the Grade if the student has not attended.
So the objective, is to disable the input field when the checkbox for "attendance" is checked

The .attr() method only manage string; So if you want to change an attribut like disabled or even checked with a boolean or something else, you have to use the prop method.
For more information check this post :
.prop() vs .attr()
You can execute the snippet below.
$("#Attendance").on("change", function () {
$("#Grade").prop("disabled", this.checked)
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form asp-action="Save" asp-controller="ClassesHeld" method="post">
<input asp-for="ClassHeldId" value="#Model.ClassHeldId" hidden />
<div class="form-group">
<label>Student</label>
<input asp-for="#Model.Student" value="#Model.Student" class="form-control" readonly />
</div>
<div class="form-group">
<label>Grade</label>
<input id="Grade"asp-for="Grade" type="number" value="#Model.Grade" class="form-control" min="0" max="5" />
</div>
<div class="form-group">
<label>Attendance</label>
<input id="Attendance" class="form-check-input" asp-for="Attendance" type="checkbox"/>
</div>
<button class="btn btn-primary" type="submit" value="Save">Save</button>
</form>
<script>
</script>

I think you actually need to remove the disabled attribute when you don't want it. Maybe try this:
$(document).ready(function() {
$("#Attendance").on("change", function () {
if (this.checked) {
$("#Grade").attr("disabled", true);
} else {
$("#Grade").removeAttr("disabled");
}
});
});

Entering data in an input and then displaying just the text entered elsewhere on page

I am creating a checkout page and I cannot figure out how to do the following. When the customer enters their shipping information, I want to display that same information further down the page in a confirmation section. I will not be submitting the information until the customer places the order, so there is no way to echo this information as I won't be submitting to my db until after they submit it.
I looked into this and I see things with a data-copy function and that is basically what I need except I do not want the copied data to show up in an input field. I just want it to display the text.
So if I had the following field:
Shipping street:
123 Main St.
I would want the 123 Main St to show up in a different section of the page.
I tried doing the data-copy function and I couldn't even get that to work. I'm not sure if this is the best method to use for this. I do not want the copied data to be editable. I have disabled that from my code.
I tried doing this:
<div class="field">
<label class="paddingleft" for="fullname">Full Name</label>
<div class="center"><input type="text" class="biginputbarinline preview" id="ShipToFullname" data-copy="name" name="ShipToFullname" required> </div>
</div>
This is the confirmation part farther down the page:
<p><input type="text" class="preview" id="name" disabled></p>
The Jquery
$(document).ready(function() {
$(".preview").keyup(function() {
var ElemId = $(this).data('copy');
$("#"+ElemId).val($(this).val());
});
});
Is there a better way I can do this and most importantly an input field not show up with the copied data?
UPDATED CODE
<div class="center">
<div class="field">
<label class="paddingleft" for="fullname">Full Name</label>
<div class="center"><input type="text" class="biginputbarinline preview" id="ShipToFullname" data-copy="#name" name="ShipToFullname" required></div>
</div>
Confirmation part
<p>Shipping to:</p>
<p><div class="preview" id="name"></div></p>
The Jquery
$(document).ready(function() {
$(".preview").on('keyup', function() {
$($(this).data('copy')).html($(this).val());
});
});

Is this what you want?
Note that data-copy="name" should now be data-copy="#name" for it to work
$(document).ready(function() {
$(".preview").on('keyup', function() {
$($(this).data('copy')).html($(this).val());
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="field">
<label class="paddingleft" for="fullname">Full Name</label>
<div class="center">
<input type="text" class="biginputbarinline preview" id="ShipToFullname" data-copy="#name" name="ShipToFullname" required>
</div>
</div>
<br>
Your name is:
<div id="name"></div>

Simply change
var ElemId = $(this).data('copy');
$("#"+ElemId).val($(this).val());
to
$('#name').val($('#ShipToFullname').val());
Basicaly it says to set the value of id nameto the value of id ShipToFullname
Here the fiddle => http://jsfiddle.net/9sgcydmg/1/
If you don't want to output the data in another input you can simply set an id to any html element and use instead:
$('#name').html($('#ShipToFullname').val());
Here the fiddle => http://jsfiddle.net/89oeyq0h/
FINAL ANSWER : in it's most simple way, using jQuery, i would do something like this:
<input onkeyup="$('#name').html(this.value)" ... />
<p id='name'></p>
<input onkeyup="$('#addr').html(this.value)" ... />
<p id='addr'></p>
and so on...
http://jsfiddle.net/oky005a0/

jQuery remove selected element, dynamically generated

I have a form and I can dynamically add more lines but if I try to remove a specific line it does not work, however the first line gets removed with no problem.
Here is the html:
<form class="order-form">
<div class="product-lines">
<!-- Product Line Section -->
<div class="product-line">
<img alt="remove" src="img/close.png" />
<input class="input-text" name="product-code" type="text" placeholder="Product Code" ></input>
<input class="input-text" name="product-quantity" type="text" placeholder="Quantity"></input>
<input class="input-text" name="product-discript" type="text" placeholder="Discription of Product"></input>
<label class="label-sign">£</label>
<input class="input-text" name="product-price" type="text" placeholder="RRP Price"></input>
<br>
</div>
</div>
<div id="product-btn">
<input name="btn-add-line" type="button" value="Add new line"></input>
<input name="btn-update" type="button" value="Update"></input>
<input name="btn-submit" type="submit" value="Submit Order"></input>
<label class="label-sign">£</label>
<input class="input-text" name="order-info" type="text" placeholder="Order total" ></input>
</div>
</form>
The jQuery code I have tried:
$(".btn-close").on("click", function(e){
$(e.currentTarget).parent().remove();
});
I've also Tried
$(e.currentTarget).parents("div.product-lines).next("div.product-line).remove();
Any help would be most appreciated, also a explanation would be very helpful for me to learn.

Try something like
$(".product-lines").on("click", ".btn-close", function(e){
$(e.currentTarget).parent().remove();
});
You cannot attach events to objects that are not currently on page (lines).
You have to attach click event on product-lines object and when it is clicked you delegate event to "closest" product-line object!

You will need to changed the jQuery slightly to allow for Event Delegation. This means all elements added in future will get the event attached to them too.
$(document).on("click", ".btn-close", function(e){
$(e.currentTarget).parent().remove();
});

$('body').on('click','button id/class',function(){
$(e.currentTarget).parent().remove();
});
but if u use this code it will remove <div class="product-line">...</div>
why you want to remove this div.
i dont get your question very well. Explain in details and step by step .

Can I recalculate a form field without a reload?

When a field in my form gets focus, I'd like a javascript function to be called that
calculates a value for that field without my putting in a specific button to do that.
Is this possible without causing the form to reload?
I have thought about making the Amount field read-only, and some other ways of doing this, but I'm looking to see if changing the Quantity field could cause the Amount field to change either using onchange in the Quantity field or onfocus in the Amount field.
Purchase Tickets<br>
<script type="text/javascript" language="JavaScript1.2">
<script type="text/javascript" language="JavaScript1.2">
document.write(
'<form name="InvGenPayTickets" action="'+PostURL+'"
onsubmit="return validateForm();" method=GET>');
</script>
<input type=hidden name="TplURL" value="GenPayCCInfo.html">
<input type=hidden name="CancelURL" value="Ooopsie.html">
<input type=hidden name="SuccessURL" value="Joanie.html">
<input type='hidden' name='TransDesc' id='TransDesc'
value="$_POST['TransDesc']; ?>" />
<input type='text' name='Quantity' id='Quantity' /> <br />
Amount<br />
$<input type='text' name='Amount' id='Amount' />
<input type="submit" value="Next">
<br>
</form>
Edit:
Here is the function that won't update. It is called if I use
<input type='text' name='Quantity'
id='Quantity' onchange="return retTotalAmt();" />
but the Amount field does not update. I am not able to update using a calc button either.
<script type="text/javascript" language="JavaScript1.2">
function retTotalAmt()
{
alert("Got here.");
var total_amt
= (document.getElementById('Quantity').value * ticketCost)
+ DonationAmount;
document.getElementById('Amount').value = total_amt;
}
</script>
Per request in comments:
<input type='text' name='Quantity'
id='Quantity' onchange="return retTotalAmt();" />
Edit -- Show Problem
<script type="text/javascript" language="JavaScript1.2">
var ticketCost = 40.00;
function EnterPage()
{
var currentTotalAmount = DonationAmount + ticketCost;
//DonationAmount moved up to ticketCost's scope fixed problem.
var DonationAmount = <?php echo($_POST['DonationAmount']); ?>;
document.getElementById('DonationAmountField').value = DonationAmount.toFixed(2);
document.getElementById('Quantity').value=1;
document.getElementById('Amount').value = currentTotalAmount.toFixed(2);
return;
}

Without using jquery:
<input type='text' name='Amount' id='Amount' onfocus="amountOnFocus();" />
Javascript:
function amountOnFocus() {
amountField = document.getElementById('Amount');
//Do calculations
amountField.value = resultOfCalculations;
}
If you wanted, you could also put a change event listener on the Quantity input so it will calculate when the value of that textbox changes.
EDIT: This onchange event works for me:
Markup:
<input type="text" id="txtChangeMe" onchange="txtChangeMeOnChange();" />
Javascript:
<script type="text/javascript">
function txtChangeMeOnChange() {
alert('changed');
}
</script>

I'm not quite sure what additional information you need, as you seem to be aware of all the ingredients for making this happen: You know that you want to detect an event, you know that you need to call a function, so I'm hoping I haven't missed something about what you're asking. I'm going to assume that you just need to know how to tie all these parts together.
The simplest example might be:
<input type="text" id="Quantity" value="10" onchange="document.getElementById('Amount').value = parseInt(document.getElementById('Quantity').value,10) * 10.0;" />
$<input type="text" id="Amount" value="100" />
though it's worth noting that this does not follow best-practices, which would involve binding an event listener separately.
On the off-chance that you accidentally typed "button" when you meant "field", I will also mention that you can update any other element's innner HTML with the ''innerHTML'' attribute, eg:
<input type="text" id="Quantity" value="10" onchange="document.getElementById('Amount').innerHTML = parseInt(document.getElementById('Quantity').value,10) * 10.0;" />
$<span id="Amount">100</span>
Of course, you can define the actual logic elsewhere, and just use ''onchange="yourFunction();"'' instead of putting everything inline, as well.
I know you mentioned "onchange" and "onfocus", though personally I tend to prefer "onkeyup", so that values will change as the user is typing.
Apologies if I've completely missed the point in your question.

Sure. Use something like this which will fire when quantity change:
$("#Quantity").change(function(){
// perform your calculations here
};
This requires the jQuery framework.

function calcPrice()
{
....
}
<input type='text' name='Quantity' id='Quantity' onchange='calcPrice();'/>
<input type='text' name='Amount' id='Amount' onfocus='calcPrice();'/>

Do you have access to jQuery? If not then you would have to bind an change event to your "quantity" input element to listen for a change of its input. Then you would simply need to modify the contents of the "amount" input.
https://developer.mozilla.org/en-US/docs/DOM/element.addEventListener
var el = document.getElementById("Amount");
el.addEventListener("change", changeAmount);
function changeAmount(){
var quantity = document.getElementById("Quantity");
quantity.value = "SET YOUR VALUE";
}

Try this solution
Html
<div class="form-group row">
<label for="inputQty" class="col-sm-4 col-form-label">Quantity</label>
<div class="col-sm-8">
<input onkeyup="CalculateItem();" onkeydown="CalculateItem();" onchange="CalculateItem();" onfocus="CalculateItem();" value="1" type="number" step="1" min="1" max="9999999" class="form-control" id="inputQty" required>
</div>
</div>
<div class="form-group row">
<label for="inputPrice" class="col-sm-4 col-form-label">Price</label>
<div class="col-sm-8">
<input onkeyup="CalculateItem();" onkeydown="CalculateItem();" onchange="CalculateItem();" onfocus="CalculateItem();" type="number" step="0.1" min="1" max="9999999" class="form-control" id="inputPrice" required>
</div>
</div>
<div class="form-group row">
<label for="inputPriceNoVat" class="col-sm-4 col-form-label">Price (no VAT)</label>
<div class="col-sm-8">
<input readonly type="text" class="form-control" id="inputPriceNoVat">
</div>
</div>
JS
<script type="text/javascript">
function CalculateItem()
{
try {
let inputPriceNoVat = $('#inputPrice').val() * $('#inputQty').val();
$('#inputPriceNoVat').val(inputPriceNoVat);
} catch (e) {
$('#inputPriceNoVat').val(0);
}
}
</script>

Javascript: Edit a preview with jquery

I have 2 divs, the first one has the label with the content to show, but when you click the "edit" button, it should show you the div="edit" and the content of the 1st label inside of the input that is linked to it (same id).
By the other way, I saw sites that when you type something inside that input, the original label of the "preview" div is getting updated in realtime.
Could someone help me with the script? Thank you!
<html>
<body>
<div id="preview">
<label id="companyName" class="workExperience">
This is my company
</label>
<label id="companyCountry" class="workExperience">
This is my company Country
</label>
<input type="button" value="edit"/>
</div>
<div id="edit">
<label>Company Name: </label>
<input type="text" id="companyName" />
<label>Company Country: </label>
<input type="text" id="companyCountry" />
</div>
</body>
</html>

You can use something like below. Notice though that I changed the id of the fields to be different. It is not a good practice to give multiple controls on the same page the same id. Some browsers do not work with this and it really doesn't make sense anyways.
$(document).ready(
function()
{
$("#companyNameText").keypress(
function()
{
$("#companyNameLabel").html(this.value);
});
$("#companyCountryText").keypress(
function()
{
$("#companyCountryLabel").html(this.value);
});
});