Develop Reference

How to control related text input element with a button?

I have a list of text-field + button that gets rendered dynamically. The user hits the button and I want to control the input field when a button is clicked.
I figure you could do something like:
<input id="1"><button onclick="doSomething(1)">Something</button>
<input id="2"><button onclick="doSomething(2)">Something</button>
<!--...-->
<input id="3"><button onclick="doSomething(3)">Something</button>
But wonder if there's a different and more sophisticated solution because the code I'm modifying passes an an anonymous function to onclick and I can't pass a unique ID like the method above.

This is very easy to achieve in vanilla Javascript (as most things). No jQuery overhead required here.
let buttons = [...document.getElementsByClassName('inputbutton')]
function doSomething(i) {
console.log(i);
}
for (const button of buttons) {
button.addEventListener('click', (e) => {
const i = e.target.previousSibling.id
doSomething(i);
})
}
<input id="1"><button class="inputbutton" type="button">Something</button>
<input id="2"><button class="inputbutton" type="button">Something</button>
<!--...-->
<input id="3"><button class="inputbutton" type="button">Something</button>

If you modify your dynamic HTML like the following and add this jQuery, you will be able to access the value of the previous input field.
var buttons = $(".inputs-and-buttons #button-after-input-field");
buttons.click(function() {
console.log($(this).prev("input").val());
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="inputs-and-buttons">
<input id="1" value="1"><button id="button-after-input-field">Something</button>
<input id="2" value="2"><button id="button-after-input-field">Something</button>
<!--...-->
<input id="3" value="3"><button id="button-after-input-field">Something</button>
</div>

You can generate dynamic Id for both input field and button with index or row number or you can add custom attribute for row number as below.
You can generate dynamic related control with specific Id for textbox and button as well. e.g. txtFirstName_1, txtLastName_1, btnAdd_1. here textbox and button distinguished by its id and number after Underscore "_" .
$(function(){
// Register click on button
//here you can pass specific class name for button if all are have same functionality
$("button").click(function(e){
console.log(this);
var btnId=$(this).attr("id");
//console.log(btnId);
// Way 1
//Split btnId with "_" e.g btn_1 will splited with ["btn","1"]
var rowIndex=btnId.split("_")[1];
console.log(btnId.split("_"),rowIndex);
$("#txt_"+rowIndex).val("Upate value by btn"+rowIndex); // Or fetch value
// Way 2
// You can directly use custom attribute data-row and do your work
var rowIndex1=$(this).attr("data-row");//$(e).prop("data-row");
console.log(rowIndex1);
//$("#txt_"+rowIndex1).val("Upate value"); // Or fetch value
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<input id="txt_1" data-row="1"><button id="btn_1" data-row="1">Something</button>
<input id="txt_2" data-row="2"><button id="btn_2" data-row="2">Something</button>
<input id="txt_3" data-row="3"> <button id="btn_3" data-row="3">Something</button>

Get dynamically value from data attribute

How do I get and store the value of the data-id attribute? The value inside of it changes on button click, so I need a method that gets the value as it changes. I've tried document.getelementbyid/name/value but I get the only get the value stored from the first button click. The method I'm using now $(this).data('id') returns nothing. Thanks
mustache file:
<td>
<form id="Form" action="./downloaddoc" method="GET">
<input type="hidden" name="p" value="download"/>
<input type="hidden" name="fileid" data-id="{{file_id}}"/>
<input class="button download_button" type="submit" value="Download">
</form>
</td>
js:
$(document).on('click', '.download_button', download_doc);
function download_doc(event) {
event.preventDefault();
var id = $(this).data('id');
console.log(id);
window.location.href = window.location.href + '?p=download&id=' + fileid;
}

You're searching for data attribute in the download button and not in the input field where it is actually present.
Add a class/id to the input field so that you can find it.
When you click on the button find the closest form and then find the input field which contains file id and extract the file id from it.
<td>
<form id="Form" action="./downloaddoc" method="GET">
<input type="hidden" name="p" value="download"/>
<!-- Added a class to the input field -->
<input type="hidden" name="field" class="input-download-file" data-id="{{file_id}}"/>
<input class="button download_button" type="submit" value="Download">
</form>
</td>
Javascript:
$(document).on('click', '.download_button', download_doc);
function download_doc(event) {
event.preventDefault();
// Find the closest form
var form = $(this).closest('form');
// Find the input field which constains the download file id
var input = $(form).find(".input-download-file");
// Get the file id
var id = $(input).data('id');
console.log(id);
window.location.href = window.location.href + '?p=download&id=' + fileid;
}

Dynamically Added Input Value disappear on next addition

I am creating a webpage with ability to add input box dynamically , everything works fine. But whenever I add a new input box the value from all the input box added above that field get cleared automatically.
Here is the html which is generated on addition of the element
<div class="main_text_area" id="got_id_from_server">
<p>Add Delay For :</p>
<div class="remove_bg button btn" name="some_id_from_server"></div>
<p>
<div contenteditable class="text_im" placeholder="Enter Delay" id="some_id_from_server" onchange="post_delay(this)"></div>
</p>
<p>
<input class="text_im" placeholder="Select" type="text" id="some_id_from_server" list="some_id_from_server" onchange="post_delay(this)">
<datalist id="some_id_from_server">
<option value="Minutes"></option>
<option value="Hours"></option>
<option value="Days"></option>
</datalist>
</p>
</div>

This behavior occurs because adding new elements to your Dom will cause the Website to kind of render the view again & again so the (in this case) not stored values of a "input field given no ID attribute" you have inputted into your input-element will just reset.
So have a look at this two code snippets:
var count = 0;
function createInput(event) {
count++;
document.body.innerHTML += "<input value='Input #"+ count + "' / >"
event.preventDefault();
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button onclick="createInput()">Create Input</button>
Edit: Using jQuery will be the better solution so have a look at this code (To prevent the reset of the input fields you have to use "append()". Try it on your own!:
var count = 0;
$(function() {
$("#createInput").click(function(event) {
count++;
$('form').append('<input type="text" value="Input #' + count + '" />');
event.preventDefault();
});
})
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form action="" method="post" name="myForm" accept-charset="utf-8">
<button id="createInput">Create Input</button>
</form>

Use JQuery to copy value from table to modal

I have a table with a list of all my data. The data is printed in a for loop so there are many rows in the table. how can i get the userid in the row with the button clicked?
<table>
<td>
<input type="hidden" value="<c:out value="${user.id}" />" name="userId" />
</td>
<td>
<button class="btn btn-default fileUpload" data-toggle="modal" id="btnUpload" data-target="#file-modal" value="<c:out value="${user.id}" />">Upload</button></td>
</table>
and i have a modal container. When the upload button in the table is clicked, the modal will open up for a file upload.
<form action="${pageContext.request.contextPath}/UserServlet" enctype="multipart/form-data" method="post">
<input type="hidden" value="5519" name="OPS" />
<input type="hidden" name="uploadUserId" />
<div class="form-group">
File : <input type="file" class="file" name="uploadFile"><br />
<button type="submit" class="btn btn-default">Upload</button>
<br /><br />
</div>
</form>
What i am trying to do is on the click of btnUpload the value in the hidden input type userId will be copied over to the hidden value type uploadUserId
I have tried doing the following but neither works
1
$(document).ready(function () {
$("#btnUpload").click(function(){
var $userId = $(this).closest("tr").find("#userId").text();
$("#uploadUserId").val($userId);
});
});
2
$(document).ready(function () {
$("#btnUpload").click(function(){
var $userId = $(this).closest("tr").children()[2].text();
$("#uploadUserId").val($userId);
});
});

This will do the trick without changing the html
$(document).ready(function () {
$("#btnUpload").click(function(){
var $userId = $(this).parent().prev("td").children("input:hidden").val();
$("#uploadUserId").val($userId);
});
});
Another solution by adding ID to the input element as shown below,
<input id="userVal" type="hidden" value="<c:out value="${user.id}" />"name="userId" />
then you can get the value from the following jquery
$("#userVal").val();

This should work. Just select and grab the user Id txt and then pass it to the uploadUserId value.
$(document).ready(function () {
$("#btnUpload").click(function(){
var $userId = $('#userId').text();
//$("#uploadUserId").val($userId);
$('input[name="uploadUserId"]').val($userId);
});
});
UPDATE
OK. I reviewed this again using your HTML structure and got this all worked out. The code below works.
$('[type="submit"]').on('click', function(e){
e.preventDefault(); // prevents the button default action. You can remove this if you want the form to submit after click.
var $userId = $(this).prev().prev().val(), // this gets the input value. based on your html it is the previous previous element.
fix1 = $userId.replace(/(?:\..+)$/, '').split('\\'), // this is a regex that replces the file extention then splits the string on the back slash turning it into an array.
fix2 = fix1.length -1; // gets the length of the array and subtracts 1 to get the last array index of the array. This i to get the file name.
$('[name="uploadUserId"').val(fix1[fix2]); // this assigns the uploadUserId value to the name of the file using the array and the index.
});

delete dynamically created textbox

I have the following code which I use to add text-boxes dynamically on click of button. It works.
<div id="forms" name="forms">
<input name="winner[]" type="text" id="tag" size="20"/><br/>
</div>
<input type="button" name="addmore" id="addmore" value="Add More Winners" onclick="addForm()"/>
The javascript for the above code is:
function addForm() {
$("#forms").append(
"<input type ='text' class='winner' name='winner[]'><br/>");
$(".winner").autocomplete("autocomplete.php", {
selectFirst: true
});
}
I am using auto complete to get data from database in the text-box
What I want is - suppose if a user clicks on add more winner button but does not want to add any data in the textbox, I should give him a button to delete the extra text-box.
How should the JavaScript be written for this?
Do see my above code

var i=0;
function addForm() {
i++;
$("#forms").append(
"<input type ='text' id='input_'"+i+" class='winner' name='winner[]'><button onclick='delete('"+i+"')' id='button_'"+i+">delete</button><br/>");
$(".winner").autocomplete("autocomplete.php", {
selectFirst: true
});
function delete(i)
{
$("#input_"+i).remove();
$("#button_"+i).remove();
}
simply use a counter to set an ID to inputs and buttons and send that counter to delete function;

Simply use the code below :
$("#forms").append("<p><input type ='text' class='winner' name='winner[]' ><button onclick='$(this).parent().remove()'>delete</button></p>");

Try this function.
function removeElement()
{
if(intTextBox != 0)
{
var contentID = document.getElementById('content');
contentID.removeChild(document.getElementById('strText'+intTextBox));
intTextBox = intTextBox-1;
}
}

Try adding a remove button while adding a text box dynamically to remove the text box if necessary
Here is the html code
<div id="forms" name="forms">
<input name="winner[]" type="text" id="tag" size="20"/><br/>
</div>
<input type="button" name="addmore" id="addmore" value="Add More Winners" />
Here is the jQuery code
$('#addmore').click(function () {
$('#forms').append('<input type ="text" class="winner" name="winner[]"><input type="button" onclick="$(this).prev().remove();$(this).remove();">');
});
Here is the demo