Develop Reference

jQuery nested functions

I am still new to JavaScript and jQuery, so I am confused as to why the following code is not working as I anticipated. All I am trying to do is save input on a button click (id=recordInput) and display it with another button click (id=displayInput). What I observe is that tempInput is stored, (the code works until that point) but assignment of displayInputs onclick attribute is not executed. My question is, can you not nest a $().click() call inside of another &().click() call?
<script>
$(document).ready(function () {
$('#recordInput').click(function(event) {
var tempInput = $('#testInput').val();
&('#displayInput').click(function(event) {
console.log(tempInput);
});
});
});
</script>
My thinking is this in pseudocode:
assign recordInput onclick attribute to the following function:
store tempInput
set displayInput onclick to alert the tempInput value
what is wrong with my thinking?
NOTE: I did not include any html tags but all of the ids are referenced correctly

It's not working because you have put & instead of $ here
$('#displayInput').click(function(event) {
Fixing this may work, but you shouldn't set event handlers this way. Because every time your first handler function is called it will set an event handler for the second one. You can try with your console.log and you will see that the number of console.log is increasing by every click on #recordInput. So you should better set it like this :
var tempInput;
$('#recordInput').click(function(event) {
tempInput = $('#testInput').val();
});
$('#displayInput').click(function(event) {
console.log(tempInput);
});

I would change
$(document).ready(function () {
$('#recordInput').click(function(event) {
var tempInput = $('#testInput').val();
&('#displayInput').click(function(event) {
console.log(tempInput);
});
});
});
to
$(function(){
var testInput = '';
$('#recordInput').click(function(){
testInput = $('#testInput').val();
});
$('#displayInput').click(function(){
if(testInput !== ''){
console.log(testInput);
}
});
});
You are using & instead of $. Of course, you don't have to format the code exactly like I did.

Unable to called mouse related event after perform Ajax for my div

I tried to use the mouseenter or other related event. But my function wont trigger. First, I have a div called article and I use jquery to append, to design its inner. But the jquery wont fired anything up. If i have mouse over.
Then I revert back to the normal mouseover and mouseout using javascript also cant work. Please explain to me why this happen and how to work around it.
I will always empty my article and perform a AJAX reload. like google search box
<div id="article"> //Empty
</div>
var over = function (myObj) {
alert("A"); //NOT FIRE
};
var out = function (myObj) {
};
$(".items").mouseenter(function() { alert("A"); //NOT Fire });
var myObject = JSON.parse(result, function (key, value) {
if (key == "Name") name = value;
if (key == "ProductId") id = value;
if (key == "Url") {
$("#article").append(
"<div class='items left' onmouseover='over(this)' onmouseout='out(this)'>" +
"<div class='clear' style='height: 2px;'></div>" +
"</div>");
}
}
//Note: After search in depth again. I realize it has something to do with delegate using on live from jquery. However, depsite that I am still unable to call those function

Try using jquery .on() method:
$(document).on('mouseenter','.items',function() {
alert("A");
});
The .on() method attaches event handlers to the currently selected set of elements in the jQuery object.

Jquery $(this).val(); on .ready not working

I'm trying to get the value of a dropdown's option (there is an id on the select markup), when opening the web page
Using
$(document).ready(function() {
$('#cat_list').ready(function(){
var category = $(this).val();
alert(category);
});
});
I get a blank alert.
But Using .change (when selecting something else inside the dropdown) the following code works perfectly with the same function
$(document).ready(function() {
$('#cat_list').change(function(){
var category = $(this).val();
alert(category);
});
});
Finally, this works using basic javascript and it gets successfully the values on open, refresh, on form submit fail, ... etc
$(document).ready(function() {
$('#cat_list').ready(function(){
var e = document.getElementById("cat_list");
var category = e.options[e.selectedIndex].value;
alert(category);
});
});
Thanks for any help on why the first version .ready + $(this).val(); fails

Correct code is:
$(document).ready(function () {
var category = $('#cat_list').val();
alert(category);
});

$(document).ready itself means the whole document (including #cat_list) is ready to be processed. why are you checking if an element is ready or not!!??
you can directly use the value of the element like
$('#cat_list').val();

The documentation says that .ready:
Specify a function to execute when the DOM is fully loaded.
And 3 possible usage cases are:
$(document).ready(handler)
$().ready(handler) (this is not recommended)
$(handler)
However you can actually assign .ready to any element and it will be triggered:
$('#cat_list').ready(function(){
});
This code is fired. BUT this inside .ready function always refers to document.
It will work this way:
$(document).ready(function() {
$('#cat_list').ready(function(){
var category = $('#cat_list').val();
alert(category);
});
});
But actually your code is overengineered:
$(document).ready(function() {
var category = $('#cat_list').val();
alert(category);
});

jQuery bind to Paste Event, how to get the content of the paste

I have a jquery token tagit plugin and I want to bind to the paste event to add items correctly.
I'm able to bind to the paste event like so:
.bind("paste", paste_input)
...
function paste_input(e) {
console.log(e)
return false;
}
How can I obtain the actual pasted content value?

There is an onpaste event that works in modern day browsers. You can access the pasted data using the getData function on the clipboardData object.
$("#textareaid").bind("paste", function(e){
// access the clipboard using the api
var pastedData = e.originalEvent.clipboardData.getData('text');
alert(pastedData);
} );
Note that bind and unbind are deprecated as of jQuery 3. The preferred call is to on.
All modern day browsers support the Clipboard API.
See also: In Jquery How to handle paste?

How about this: http://jsfiddle.net/5bNx4/
Please use .on if you are using jq1.7 et al.
Behaviour: When you type anything or paste anything on the 1st textarea the teaxtarea below captures the cahnge.
Rest I hope it helps the cause. :)
Helpful link =>
How do you handle oncut, oncopy, and onpaste in jQuery?
Catch paste input
EDIT:
Events list within .on() should be space-separated. Refer https://api.jquery.com/on/
code
$(document).ready(function() {
var $editor = $('#editor');
var $clipboard = $('<textarea />').insertAfter($editor);
if(!document.execCommand('StyleWithCSS', false, false)) {
document.execCommand('UseCSS', false, true);
}
$editor.on('paste keydown', function() {
var $self = $(this);
setTimeout(function(){
var $content = $self.html();
$clipboard.val($content);
},100);
});
});

I recently needed to accomplish something similar to this. I used the following design to access the paste element and value. jsFiddle demo
$('body').on('paste', 'input, textarea', function (e)
{
setTimeout(function ()
{
//currentTarget added in jQuery 1.3
alert($(e.currentTarget).val());
//do stuff
},0);
});

Another approach:
That input event will catch also the paste event.
$('textarea').bind('input', function () {
setTimeout(function () {
console.log('input event handled including paste event');
}, 0);
});

On modern browsers it's easy: just use the input event along with the inputType attribute:
$(document).on('input', 'input, textarea', function(e){
if (e.originalEvent.inputType == 'insertFromPaste') {
alert($(this).val());
}
});
https://codepen.io/anon/pen/jJOWxg

$(document).ready(function() {
$("#editor").bind('paste', function (e){
$(e.target).keyup(getInput);
});
function getInput(e){
var inputText = $(e.target).html(); /*$(e.target).val();*/
alert(inputText);
$(e.target).unbind('keyup');
}
});

This work on all browser to get pasted value. And also to creating common method for all text box.
$("#textareaid").bind("paste", function(e){
var pastedData = e.target.value;
alert(pastedData);
} )

You could compare the original value of the field and the changed value of the field and deduct the difference as the pasted value. This catches the pasted text correctly even if there is existing text in the field.
http://jsfiddle.net/6b7sK/
function text_diff(first, second) {
var start = 0;
while (start < first.length && first[start] == second[start]) {
++start;
}
var end = 0;
while (first.length - end > start && first[first.length - end - 1] == second[second.length - end - 1]) {
++end;
}
end = second.length - end;
return second.substr(start, end - start);
}
$('textarea').bind('paste', function () {
var self = $(this);
var orig = self.val();
setTimeout(function () {
var pasted = text_diff(orig, $(self).val());
console.log(pasted);
});
});

It would appear as though this event has some clipboardData property attached to it (it may be nested within the originalEvent property). The clipboardData contains an array of items and each one of those items has a getAsString() function that you can call. This returns the string representation of what is in the item.
Those items also have a getAsFile() function, as well as some others which are browser specific (e.g. in webkit browsers, there is a webkitGetAsEntry() function).
For my purposes, I needed the string value of what is being pasted. So, I did something similar to this:
$(element).bind("paste", function (e) {
e.originalEvent.clipboardData.items[0].getAsString(function (pStringRepresentation) {
debugger;
// pStringRepresentation now contains the string representation of what was pasted.
// This does not include HTML or any markup. Essentially jQuery's $(element).text()
// function result.
});
});
You'll want to perform an iteration through the items, keeping a string concatenation result.
The fact that there is an array of items makes me think more work will need to be done, analyzing each item. You'll also want to do some null/value checks.

I do it like so, this would work on most browsers used by humans
$("#couponCode").bind("change keyup input paste",function () {
const value= document.getElementById("couponCode").value;
});

How to display a confirmation dialog when clicking an <a> link?

I want this link to have a JavaScript dialog that asks the user “Are you sure? Y/N”.
Link
If the user clicks “Yes”, the link should load, if “No” nothing will happen.
I know how to do that in forms, using onclick running a function that returns true or false. But how do I do this with an <a> link?

Inline event handler
In the most simple way, you can use the confirm() function in an inline onclick handler.
Link
Advanced event handling
But normally you would like to separate your HTML and Javascript, so I suggest you don't use inline event handlers, but put a class on your link and add an event listener to it.
Link
...
<script type="text/javascript">
var elems = document.getElementsByClassName('confirmation');
var confirmIt = function (e) {
if (!confirm('Are you sure?')) e.preventDefault();
};
for (var i = 0, l = elems.length; i < l; i++) {
elems[i].addEventListener('click', confirmIt, false);
}
</script>
This example will only work in modern browsers (for older IEs you can use attachEvent(), returnValue and provide an implementation for getElementsByClassName() or use a library like jQuery that will help with cross-browser issues). You can read more about this advanced event handling method on MDN.
jQuery
I'd like to stay far away from being considered a jQuery fanboy, but DOM manipulation and event handling are two areas where it helps the most with browser differences. Just for fun, here is how this would look with jQuery:
Link
...
<!-- Include jQuery - see http://jquery.com -->
<script type="text/javascript">
$('.confirmation').on('click', function () {
return confirm('Are you sure?');
});
</script>

You can also try this:
<a href="" onclick="if (confirm('Delete selected item?')){return true;}else{event.stopPropagation(); event.preventDefault();};" title="Link Title">
Link Text
</a>

I'd suggest avoiding in-line JavaScript:
var aElems = document.getElementsByTagName('a');
for (var i = 0, len = aElems.length; i < len; i++) {
aElems[i].onclick = function() {
var check = confirm("Are you sure you want to leave?");
if (check == true) {
return true;
}
else {
return false;
}
};
}​
JS Fiddle demo.
The above updated to reduce space, though maintaining clarity/function:
var aElems = document.getElementsByTagName('a');
for (var i = 0, len = aElems.length; i < len; i++) {
aElems[i].onclick = function() {
return confirm("Are you sure you want to leave?");
};
}
JS Fiddle demo.
A somewhat belated update, to use addEventListener() (as suggested, by bažmegakapa, in the comments below):
function reallySure (event) {
var message = 'Are you sure about that?';
action = confirm(message) ? true : event.preventDefault();
}
var aElems = document.getElementsByTagName('a');
for (var i = 0, len = aElems.length; i < len; i++) {
aElems[i].addEventListener('click', reallySure);
}
JS Fiddle demo.
The above binds a function to the event of each individual link; which is potentially quite wasteful, when you could bind the event-handling (using delegation) to an ancestor element, such as the following:
function reallySure (event) {
var message = 'Are you sure about that?';
action = confirm(message) ? true : event.preventDefault();
}
function actionToFunction (event) {
switch (event.target.tagName.toLowerCase()) {
case 'a' :
reallySure(event);
break;
default:
break;
}
}
document.body.addEventListener('click', actionToFunction);
JS Fiddle demo.
Because the event-handling is attached to the body element, which normally contains a host of other, clickable, elements I've used an interim function (actionToFunction) to determine what to do with that click. If the clicked element is a link, and therefore has a tagName of a, the click-handling is passed to the reallySure() function.
References:
addEventListener().
Conditional ('ternary') operator.
confirm().
getElementsByTagName().
onclick.
if () {}.

Confirm OK, then goto URL (uses onclick())

jAplus
You can do it, without writing JavaScript code
<head>
<script src="/path/to/jquery.js" type="text/javascript" charset="utf-8"></script>
<script src="/path/to/jquery.Aplus.js" type="text/javascript" charset="utf-8"></script>
</head>
<body>
...
Link
...
</body>
Demo page

This method is slightly different than either of the above answers if you attach your event handler using addEventListener (or attachEvent).
function myClickHandler(evt) {
var allowLink = confirm('Continue with link?');
if (!allowLink) {
evt.returnValue = false; //for older Internet Explorer
if (evt.preventDefault) {
evt.preventDefault();
}
return false;
}
}
You can attach this handler with either:
document.getElementById('mylinkid').addEventListener('click', myClickHandler, false);
Or for older versions of internet explorer:
document.getElementById('mylinkid').attachEvent('onclick', myClickHandler);

Just for fun, I'm going to use a single event on the whole document instead of adding an event to all the anchor tags:
document.body.onclick = function( e ) {
// Cross-browser handling
var evt = e || window.event,
target = evt.target || evt.srcElement;
// If the element clicked is an anchor
if ( target.nodeName === 'A' ) {
// Add the confirm box
return confirm( 'Are you sure?' );
}
};
This method would be more efficient if you had many anchor tags. Of course, it becomes even more efficient when you add this event to the container having all the anchor tags.

USING PHP, HTML AND JAVASCRIPT for prompting
Just if someone looking for using php, html and javascript in a single file, the answer below is working for me.. i attached with the used of bootstrap icon "trash" for the link.
<a class="btn btn-danger" href="<?php echo "delete.php?&var=$var"; ?>" onclick="return confirm('Are you sure want to delete this?');"><span class="glyphicon glyphicon-trash"></span></a>
the reason i used php code in the middle is because i cant use it from the beginning..
the code below doesnt work for me:-
echo "<a class='btn btn-danger' href='delete.php?&var=$var' onclick='return confirm('Are you sure want to delete this?');'><span class='glyphicon glyphicon-trash'></span></a>";
and i modified it as in the 1st code then i run as just what i need.. I hope that can i can help someone inneed of my case.

Most browsers don't display the custom message passed to confirm().
With this method, you can show a popup with a custom message if your user changed the value of any <input> field.
You can apply this only to some links, or even other HTML elements in your page. Just add a custom class to all the links that need confirmation and apply use the following code:
$(document).ready(function() {
let unsaved = false;
// detect changes in all input fields and set the 'unsaved' flag
$(":input").change(() => unsaved = true);
// trigger popup on click
$('.dangerous-link').click(function() {
if (unsaved && !window.confirm("Are you sure you want to nuke the world?")) {
return; // user didn't confirm
}
// either there are no unsaved changes or the user confirmed
window.location.href = $(this).data('destination');
});
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="text" placeholder="Nuclear code here" />
<a data-destination="https://en.wikipedia.org/wiki/Boom" class="dangerous-link">
Launch nuke!
</a>
Try changing the input value in the example to get a preview of how it works.