Develop Reference

Get id of active textfield

If I have 4 text boxes in my form, at any point can I get id of text field in which user is filling the information at the moment.
Eg. in following context, I should be able to get id of textbox 3.
Thanks

You can get the currently active element using document.activeElement, so its ID using document.activeElement.id.
Focus on any of the textboxes in the snippet to see how it works:
setInterval(function() {
console.log("Active element: " + document.activeElement.id);
},1000);
<input type="text" name="" id="1">
<br>
<input type="text" name="" id="2">
<br>
<input type="text" name="" id="3">
<br>
<input type="text" name="" id="4">

You can use getAttribute() like the following way:
function myFunc(thatText){
console.log(thatText.getAttribute('id'));
}
<div>
<input type="text" id="txt1" onchange="myFunc(this)" placeholder="1"/><br/>
<input type="text" id="txt2" onchange="myFunc(this)" placeholder="2"/><br/>
<input type="text" id="txt3" onchange="myFunc(this)" placeholder="3"/><br/>
<input type="text" id="txt4" onchange="myFunc(this)" placeholder="4"/>
</div>

There can be an onkeyup function. pass this from the DOM and in js use that argument to get id
function getElem(elem) {
console.log(elem.id)
}
<input type="text" name="test" id="1" onkeyup="getElem(this)">
<br>
<input type="text" name="test" id="2" onkeyup="getElem(this)">
<br>
<input type="text" name="test" id="3" onkeyup="getElem(this)">
<br>
<input type="text" name="test" id="4" onkeyup="getElem(this)">

jQuery to populate array-named form fields based on first entered text box value

I have a form with variable number of inputs as an array
<form>
<label for="same">all the same as first?</label>
<input type="text" id="foo[1]" name="foo[1]" value="" />
<input type="text" id="foo[2]" name="foo[2]" value="" />
<input type="text" id="foo[3]" name="foo[3]" value="" />
<input type="text" id="foo[4]" name="foo[4]" value="" />
<input type="text" id="foo[5]" name="foo[5]" value="" />
</form>
The idea is when i put some value in the first field (foo[1]) i need the jQuery or Javascript copy the value from #foo[1] into #foo[2], #foo[3], etc depending on the array.

Do you need following behavior :
$(document).ready(function(){
$("input[id^=foo\\[]").prop("disabled",true); //disable all elements first
$("input#foo\\[1\\]").prop("disabled",false); //then enable the first one
$("input#foo\\[1\\]").change(function(){
var source = $(this);
var currentVal = $(source).val();
$("input[id^=foo\\[]").each(function(){
if(!$(this).is(source))
$(this).val(currentVal);
});
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<form>
<label for="same">all the same as first?</label>
<input type="text" id="foo[1]" name="foo[1]" value="" />
<input type="text" id="foo[2]" name="foo[2]" value=""/>
<input type="text" id="foo[3]" name="foo[3]" value=""/>
<input type="text" id="foo[4]" name="foo[4]" value=""/>
<input type="text" id="foo[5]" name="foo[5]" value=""/>
</form>

$('input').on('input', function(){
$(this).siblings().val($(this).val());
});
Couldn't tell if you just wanted the first or all. If just the first, you can target with an id or jQuery.
$('input').eq(0).on('input', function(){});

Something like this
HTML
<form>
<label for="same">all the same as first?</label>
<input type="text" id="foo[1]" name="foo[1]" value="" />
<input type="text" id="foo[2]" name="foo[2]" value="" />
<input type="text" id="foo[3]" name="foo[3]" value="" />
<input type="text" id="foo[4]" name="foo[4]" value="" />
<input type="text" id="foo[5]" name="foo[5]" value="" />
</form>
JavaScript
$("input[id=foo\\[1\\]").on("input", function (){
$(this).siblings().val($(this).val());
});
And if you want the other to be readonly:
$("input[id^=foo\\[]:not([id=foo\\[1\\]])").attr("readonly", "readonly");

JavaScript/Jquery : Multiple input value with multiple id

I have one html form
<form>
<input type="hidden" name="id" value="1" /><input type="text" name="qty" />
<input type="hidden" name="id" value="2" /><input type="text" name="qty" />
<input type="hidden" name="id" value="3" /><input type="text" name="qty" />
<input type="hidden" name="id" value="4" /><input type="text" name="qty" />
<input type="submit"/>
</form>
When I submit form,Say for id = 1 , qty is 5 or for id = 3, qty is 8. How to get this values in java script or jquery and submit this information to server? I get all the input text values. But I cannot differentiate which qty is for which value?

You should not have two or more elements with the same name or id!
names & ids are meant to be unique.
try this:
<form>
<input type="hidden" name="id[1]" value="1" /><input type="text" name="qty[1]" id="qty1" value="" />
<input type="hidden" name="id[2]" value="2" /><input type="text" name="qty[2]" id="qty2" value="" />
<input type="hidden" name="id[3]" value="3" /><input type="text" name="qty[3]" id="qty3" value="" />
<input type="hidden" name="id[4]" value="4" /><input type="text" name="qty[4]" id="qty4" value="" />
<input type="submit"/>
</form>
You can acces the data in JS like this:
using the element name:
var qty1 = document.forms[0].elements["qty[1]"].value;
Using the element id:
var qty1 = document.getElementById("qt1").value;

Well, to me, your hidden inputs are useless : You say that for input text one is a corresponding hidden field id with a defined value. Then you just have to name your input correctly and you know which id or something is correspondant.
If you want to use jQuery (javascript) as you said, then just do something like this :
<form>
<input type="text" name="qty1" id="qty1" />
<input type="text" name="qty2" id="qty2" />
<input type="text" name="qty3" id="qty3" />
<input type="text" name="qty4" id="qty4" />
<input type="submit" name='submit' id="submitButton" value="submit"/>
</form>
<script>
$('document').on('click','#submitButton',function(event){
event.preventDefault();
//this prevents the click to submit, as you want to get values by javascript... remove this if you post it with php
console.log('QTY1 : '+$('#qty1').val()+' - QTY2 : '+$('#qty2').val()+' - QTY3 : '+$('#qty3').val()+' - QTY 4 : '+$('#qty4').val());
//This is with jQuery, javascript would look like addEventListeneer, and get values like document.getElementById('id').value;
//then, ajax something if you really want to post your form through javascript, but this is not a good solution...
});
</script>
Other solution, better to me, would be just to use php and post directly your form...
<?php
if(isset($_POST['submit'])){
//then, user has clicked on submit button
//CONSIDERED THAT YOU HAVE CHECKED IF THE FIELDS ARE NOT EMPTY
$qty1 = $_POST['qty1'];
$qty2 = $_POST['qty2'];
$qty3 = $_POST['qty3'];
$qty4 = $_POST['qty4'];
//do your stuff with the posted values...
}else{
echo '
<form method="POST" action="yourPage.php">
<input type="text" name="qty1" id="qty1" />
<input type="text" name="qty2" id="qty2" />
<input type="text" name="qty3" id="qty3" />
<input type="text" name="qty4" id="qty4" />
<input type="submit" name="submit" id="submitButton" value="submit"/>
</form>
';
}
?>
Hope it helps

Your html is perfectly valid, but you're not using the name of the elements to your advantage.
<input type="hidden" name="id1" value="1" /><input type="text" name="qty1" />
This will return:
id1=1&qty1=X
But in the end I think your hidden field is just wasting space. All you seem to need is the quantity field with a proper name.
<input type="text" name="qty1" />
<input type="text" name="qty2" />
...
If you use the same name for the elements it will still give you the desired data, but it might need some parsing to figure out "what is what".
<input type="text" name="qty" />
<input type="text" name="qty" />
...
This will basically return:
qty=X,Y (or qty=X&qty=Y)
item ----0-1

You could wrap each pair of hidden-text inputs in div element, then iterate through these divs and find these two inputs inside each of the div elements. It might look like this:
<form>
<div id="keyValuePairs">
<div class="pair">
<input type="hidden" name="id" value="1" /><input type="text" name="qty" />
</div>
<div class="pair">
<input type="hidden" name="id" value="2" /><input type="text" name="qty" />
</div>
<div class="pair">
<input type="hidden" name="id" value="3" /><input type="text" name="qty" />
</div>
<div class="pair">
<input type="hidden" name="id" value="4" /><input type="text" name="qty" />
</div>
</div>
<input type="submit" id="sendBtn"/>
</form>
Then iterate with Jquery
$("#sendBtn").click(function(){
var arr = [];
$("#keyValuePairs .pair").each(function(){
var val = $(this).find("input[name='id']").val();
var key = $(this).find("input[name='qty']").text();
var obj = { val:val, key:key };
arr.push(obj);
});
// some ajax call or any way you want to post data server
});
at the end of iteration, arr should contain objects with val property containing what is in the value property of hidden input, and key property containing what the text present in text inputs.

only first form is checked by jQuery

i have one form on my page. so i want to check each input with corresponding button. so i wrote smth like this and it only checks first input even if i click on second inputs button.
<form target="myFrame" method="post" id="addProduct">
<fieldset>
<input type="hidden" name="iProductAdd" value="6" />
<input type="number" onkeypress="return isNumberKey(event)" name="aProducts[6]" autocomplete="off" value="" maxlength="4" size="4" onclick="function()" class="quantity" />
<input type="submit" onclick="refreshIframe();" value="" class="addtobasket" id="addtobasket" />
</fieldset>
<fieldset>
<input type="hidden" name="iProductAdd" value="7" />
<input type="number" onkeypress="return isNumberKey(event)" name="aProducts[7]" autocomplete="off" value="" maxlength="4" size="4" onclick="function()" class="quantity" />
<input type="submit" onclick="refreshIframe();" value="" class="addtobasket" id="addtobasket" />
</fieldset>
<fieldset>
<input type="hidden" name="iProductAdd" value="4" />
<input type="number" onkeypress="return isNumberKey(event)" name="aProducts[4]" autocomplete="off" value="" maxlength="4" size="4" onclick="function()" class="quantity" />
<input type="submit" onclick="refreshIframe();" value="" class="addtobasket" id="addtobasket" />
</fieldset>
</form>
and i have jQuery Code:
$(document).ready(function(){
$("form").submit(function(){
// Get the Login Name value and trim it
var name = $.trim($('.quantity').val());
// Check if empty of not
if (name === '') {
$("#addtobasket").css("background-image", "url('http://restorani.weby.biz/templates/default/img/tick-red.png')");
return false;
} else {
$('input[type="submit"]').each(function(){
$("#addtobasket").css("background-image", "url('http://restorani.weby.biz/templates/default/img/tick-green.png')");
});
}
});
});

Your problem is that you are using ids as it were classes. An id should be unique in a document. So defining multiple objects with the same id is an error. And all functions will apply only the first they encounter. To do what you want, you have to use classes, so change your code in this way:
$(".addtobasket").css("background-image", "url('http://restorani.weby.biz/templates/default/img/tick-green.png')");
To look for all elements of that class.

How to clone/copy the value of several input inside in one single input

Hello I need this for my school project.
I want JAVASCRIPT to copy/Clone the values of 4 or 5 input fields, when typing content inside of them into one single input.
this is the input that must collect all values:
<input type="hidden" id="mainInput" name="main" value="" />
This is the rest inputs
<input type="text" id="input1" name="input1" value="info1" />
<input type="text" id="input2" name="input2" value="hello World" />
<input type="text" id="input3" name="input3" value="my SECOND" />
<input type="text" id="input4" name="input4" value="sure!" />
So in the final step, the result must be this:
<input type="hidden" id="mainInput" name="main" value="info1hello Worldmy SECONDsure!" />
PS this must happen without any submit buttons... There is a option called onFocus in JS.
So any ideas?

$('input[type="text"]').keydown(function () {
$('#mainInput').val($('#input1').val() + $('#input2').val() + $('#input3').val() + $('#input4').val())
})
jsFiddle example

You can try this method and works fine jsfiddle
<input type="text" class="testvalues" id="input1" name="input1" value="info1" />
<input type="text" class="testvalues" id="input2" name="input2" value="hello World" />
<input type="text" class="testvalues" id="input3" name="input3" value="my SECOND" />
<input type="text" class="testvalues" id="input4" name="input4" value="sure!" />
<input type="hidden" id="mainInput" name="main" value="" />
$('.testvalues').on('keyup',function(){
var txtfirst=$('#input1').val();
var txtsecond=$('#input2').val();
var txtthird=$('#input3').val();
var txtfourth=$('#input4').val();
$('#mainInput').val(txtfirst +" "+ txtsecond +" "+ txtthird +" "+ txtfourth );
});
Look at fiddle at http://jsfiddle.net/HGu5M/22/

$('input[type="text"]').change(function () {
$('#mainInput').val($('#input1').val() + $('#input2').val() + $('#input3').val() + $('#input4').val());
})