Develop Reference

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.

number increment button

I have an existing html form which use array to store multiple row values. So I do not have a specific name for the same field for different row. In the PHP page i match the row according to the index.
In the form below, how do I make the button + and - to increase and decrease the value of the quantity of the specific row?
ROW 1
<input type="text" name="product[]" />
<input type="text" name="price[]" value="" onChange="updatePrice()" />
<input type="text" name="quantity[]" value="" onChange="updatePrice()" />
<input type="button" onclick="inc(this)" value="+"/>
<input type="button" onclick="dec(this)" value="-"/>`
ROW 2
<input type="text" name="product[]" />
<input type="text" name="price[]" value="" onChange="updatePrice()" />
<input type="text" name="quantity[]" value="" onChange="updatePrice()" />
<input type="button" onclick="inc(this)" value="+"/>
<input type="button" onclick="dec(this)" value="-"/>
ROW 3
<input type="text" name="product[]" />
<input type="text" name="price[]" value="" onChange="updatePrice()" />
<input type="text" name="quantity[]" value="" onChange="updatePrice()" />
<input type="button" onclick="inc(this)" value="+"/>
<input type="button" onclick="dec(this)" value="-"/>

In my opinion you first should to numerate items:
<input type="text" name="product[]" />
<input id="price-1" type="text" name="price[]" value="" onChange="updatePrice(1)" /> <!-- row number -->
<input id="qty-1" type="text" name="quantity[]" value="" onChange="updatePrice(1)" />
<input type="button" onclick="inc('qty-1')" value="+"/>
<input type="button" onclick="dec('qty-1')" value="-"/>
Then use javascript to manipulate items:
<script>
function inc(id) {
stepQty(id, +1);
}
function dec(id) {
stepQty(id, -1);
}
function stepQty(id, step) {
var value = $('#'+id).val();
$('#'+id).val(value + step);
}
function updatePrice(id) {
var a = $('#price-'+id).val() || 0;
var b = $('#qty-'+id).val() || 0;
$('#'+id).val(a*b);
}
</script>

Clearing the textbox values onclick and displaying onblur

Is there a way to clear the default textbox value onclick on textbox and display onblur of multiple textboxes on form page?

HTML:
<input type="text" value="" onClick="Clear();" id="textbox1>
<input type="text" value="" onClick="Clear();" id="textbox2>
<input type="text" value="" onClick="Clear();" id="textbox3>
<input type="text" value="" onClick="Clear();" id="textbox4>
Javascript :
function Clear()
{
document.getElementById("textbox1").value= "";
document.getElementById("textbox2").value= "";
document.getElementById("textbox3").value= "";
document.getElementById("textbox4").value= "";
}
Your question was a little vague to me, but the above will clear all the textboxes when one is clicked. Hopefully this helps you.

One Line solution
<input type="text" value="" onClick="this.value='';" id="textbox1">
or
<input type="text" value="" onClick="this.value=='Initial Text'?this.value='':this.value;" id="textbox1">

function Clear1(str)
{
document.getElementById(str).value= "";
}
function Clear2(str2)
{
var aa1=document.getElementById(str2);
if (aa1.value==""){
document.getElementById(str2).style.backgroundColor = "#ffcccc";
}else{
document.getElementById(str2).style.backgroundColor = "#ffffff";
}
}
<input type="text" value="test1" onClick="Clear1(this.id);" id="textbox1" onblur="Clear2(this.id);">
<input type="text" value="test2" onClick="Clear1(this.id);" id="textbox2" onblur="Clear2(this.id);">
<input type="text" value="test3" onClick="Clear1(this.id);" id="textbox3" onblur="Clear2(this.id);">
<input type="text" value="test4" onClick="Clear1(this.id);" id="textbox4" onblur="Clear2(this.id);">
https://jsfiddle.net/warunamanjula/qy0hvmyq/1/

How to assign a javascript variable to input text field?

I've a variable called "numbers" in javascript and this variables holds 10 numbers from 0 to 9 as shown below.
var numbers = "0123456789";
Now what I want to be able to do is assigning each of these numbers to an input text field using document.getElementByID("a") = "";, for example:
<input type="text" id="a" value="" />
<input type="text" id="b" value="" />
<input type="text" id="c" value="" />
<input type="text" id="d" value="" />
<input type="text" id="e" value="" />
<input type="text" id="f" value="" />
<input type="text" id="g" value="" />
<input type="text" id="h" value="" />
<input type="text" id="i" value="" />
<input type="text" id="j" value="" />
Currently the following text fields above holding no values, but I want to be able to assign each of the numbers in variable "numbers" to each of the text fields above, so it would looks like this when user clicks on a button called click me.
<input type="text" id="a" value="0" />
<input type="text" id="b" value="1" />
<input type="text" id="c" value="2" />
<input type="text" id="d" value="3" />
<input type="text" id="e" value="4" />
<input type="text" id="f" value="5" />
<input type="text" id="g" value="6" />
<input type="text" id="h" value="7" />
<input type="text" id="i" value="8" />
<input type="text" id="j" value="9" />
Also is there any way to leave a text field empty if a particular number is = 0
Thanks in advance :)

var numbers = "0123456789";
var ids = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j"];
for (var i = 0; i < ids.length; i++)
{
var el = document.getElementById(ids[i]);
var num = numbers[i];
if (num == "0")
el.value = "";
else
el.value = num;
}
Working sample: http://jsfiddle.net/LrJ5S/.

In addition to mellamokb, another way of accomplishing the same:
var numbers = "abc0123abc0123";
var inputs = document.getElementsByTagName('input');
var i = 0;
for(var s = 0; s < inputs.length; s++) {
inputs[s].value = numbers.charAt(i)!=0?numbers.charAt(i):'';
i++;
}
JSFiddle

Basic example with no checks on data size of inputs and string:
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title></title>
</head>
<body>
<div id="myInputs">
<input type="text" id="a" value="" />
<input type="text" id="b" value="" />
<input type="text" id="c" value="" />
<input type="text" id="d" value="" />
<input type="text" id="e" value="" />
<input type="text" id="f" value="" />
<input type="text" id="g" value="" />
<input type="text" id="h" value="" />
<input type="text" id="i" value="" />
<input type="text" id="j" value="" />
</div>
<button id="run">Run</button>
<script type="text/javascript">
function putNumbers(){
var numbers = "0123456789";
var inputs = document.getElementById("myInputs").getElementsByTagName("input");
for(var i=0;i<inputs.length;i++){
var val = numbers.charAt(i);
inputs[i].value = val==="0"?"":val;
}
}
document.getElementById("run").onclick = putNumbers;
</script>
</body>
</html>
working Example