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.each + .click (jQuery)

If I try to run this code:
$('a').each( function(index, element) {
element.click(function(){
console.log('hit');
});
});
It doesn't work, but if I code this one:
$('a').each( function() {
$(this).click(function(){
console.log('hit');
});
});
Everything is ok, someone can help me please? Why is not working when I use element
PD: I know that this solution is the best but I would like to know why is not working before
$('a')click(function(){
console.log('hit');
});

It should be $(element).click(... because element is a DOM Element, not a jQuery object.
$('a').each( function(index, element) {
$(element).click(function(){
console.log('hit');
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p><a>foo</a>
<p><a>bar</a>
<p><a>baz</a>
There is actually a click method on native Elements, but it serves a different purpose; it invokes a "click" event instead of binding a handler.
And of course to do this without large dependencies, and using modern syntax, it could look like this:
for (const element of document.querySelectorAll('a')) {
element.addEventListener("click", handler)
}
function handler() {
console.log('hit');
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p><a>foo</a></p>
<p><a>bar</a></p>
<p><a>baz</a></p>

You can use addEventListener
$('a').each( function(index, element) {
element.addEventListener("click", function(){
console.log('hit');
});
});

Remove/add a class and then execute an event on this new class

I use this script to change a class:
$('.fa.fa-plus-circle').each(function() {
$(this).on('click', function () {
$(this).removeClass().addClass("fa fa-minus-circle");
});
});
Then I used
$('.fa.fa-minus-circle').each(function () {
$(this).on('click', function () {
$(this).removeClass().addClass("fa fa-plus-circle");
});
});
So for the first one "fa.fa-plus-circle" that is the default when the page is loading, everything is good and the class changes. But when the class changes I can't do anything else after, JQuery continues to execute
$('.fa.fa-plus-circle').each(function() {
$(this).on('click', function () {
$(this).removeClass().addClass("fa fa-minus-circle");
});
});
Why ??
Thanks in advance

You need to use delegate for this, because you are adding the classes dynamically.
$(document).on("click", '.fa.fa-minus-circle', function() {
$(this).removeClass().addClass("fa fa-plus-circle");
});
$(document).on("click", '.fa.fa-plus-circle', function() {
$(this).removeClass().addClass("fa fa-minus-circle");
});
Also there is no need for looping through the elements for binding the event.
But the recommended approach will be,
$('.fa').click(function() {
$(this).toggleClass("fa-minus-circle fa-plus-circle");
});
Edit
$(document).on("click", ".fa", function() {
$(this).toggleClass("fa-minus-circle fa-plus-circle");
});

It's not .fa-minus-circle when it loads, so the each loop never happens. Even if you removed the each loop (which isn't required) it wouldn't add the listeners because it wouldn't find the selector. So, you have to use the delegates version of on which looks something like this...
$('body').on('click','.fa-minus-circle',function () {
$(this).removeClass().addClass("fa fa-minus-circle");
});
fwiw, you could just use one class and toggleClass Then put all your fa-plus-circle code into the fa class since that is the default behavior.
$('body').on('click','.fa',function () {
$(this).toggleClass("fa-minus-circle");
});

There's a benefit to not removing all classes. There seems no point to removing .fa so that you can add it. Which means that your code should be:
$(function() {
$(document).on("click", '.fa.fa-minus-circle', function() {
$(this).removeClass('fa-minus-circle').addClass("fa-plus-circle");
});
$(document).on("click", '.fa.fa-plus-circle', function() {
$(this).removeClass('fa-plus-circle').addClass("fa-minus-circle");
});
});
And as #AnoopJoshi has pointed out, you can use the .toggleClass() method:
$(function() {
$('.fa').on('click', function() {
$(this).toggleClass('fa-minus-circle fa-plus-circle');
});
});

How to simulate a click event when document onready?

The two method below are not working for me; I need the button click event to fire with the document onready event. (#usrpost is a button element.)
$(function() {
$("#usrpost").trigger("click");
$("#usrpost").live("click",function() {
//do something.
});
});
I've also tried the following:
$(function() {
$("#usrpost")[0].click();
$("#usrpost").live("click",function() {
//do something.
});
});

You need to trigger the event after the handler is added(apart from the spelling issue, also assuming you are using jQuery < 1.9)
$(function () {
$("#usrpost").live("click", function () {
//do something.
});
//fire it after the handler is added
$("#usrpost").click();
});
Note: If you are using jQuery >= 1.7 use .on() instead of .live()

$(function() {
$("#usrpost").on("click", function() {
//do something.
});
$("#usrpost").click();
});
You had a typo in "function"

You must call the .click() after bind the event:
$(function() {
$("#usrpost").live("click",function() {
//do something.
});
$("#usrpost")[0].click();
});
.live() is also now deprecated in favour of .on():
$(function() {
$('body').on('click', "#usrpost", function() {
//do something.
});
$("#usrpost")[0].click();
});

You can trigger the event too
$("#usrpost").trigger("click");

prevent double clicks on links with jQuery

What's the best way to prevent a double-click on a link with jQuery?
I have a link that triggers an ajax call and when that ajax call returns it shows a message.
The problem is if I double-click, or click it twice before the ajax call returns, I wind up with two messages on the page when I really want just one.
I need like a disabled attribute on a button. But that doesn't work on links.
$('a').on('click', function(e){
e.preventDefault();
//do ajax call
});

You can use data- attributes, something like this:
$('a').on('click', function () {
var $this = $(this);
var alreadyClicked = $this.data('clicked');
if (alreadyClicked) {
return false;
}
$this.data('clicked', true);
$.ajax({
//some options
success: function (data) { //or complete
//stuff
$this.data('clicked', false);
}
})
});

I came with next simple jquery plugin:
(function($) {
$.fn.oneclick = function() {
$(this).one('click', function() {
$(this).click(function() { return false; });
});
};
// auto discover one-click elements
$(function() { $('[data-oneclick]').oneclick(); });
}(jQuery || Zepto));
// Then apply to selected elements
$('a.oneclick').oneclick();
Or just add custom data atribute in html:
<a data-oneclick href="/">One click</a>

You need async:false
By default, all requests are sent asynchronously (i.e. this is set to true by default). If you need synchronous requests, set this option to false.
$.ajax({
async: false,
success: function (data) {
//your message here
}
})

you can use a dummy class for this.
$('a#anchorID').bind('click',function(){
if($(this).hasClass('alreadyClicked')){
return false;
}else{
$(this).addClass('alreadyClicked);
$/ajax({
success: function(){$('a#anchorID').removeClass('alreadyClicked');},
error: function(){$('a#anchorID').removeClass('alreadyClicked');}
});
}});

Check this example. You can disable the button via CSS attribute after the first click (and remove this attribute after an ajax request or with a setTimeout) or use the jQuery.one() function to remove the trigger after the first click (without disabling the button)
var normal_button = $('#normal'),
one_button = $('#one'),
disabled_button = $('#disabled'),
result = $('#result');
normal_button.on('click', function () {
result.removeClass('hide').append(normal_button.html()+'<br/>');
});
one_button.one('click', function () {
result.removeClass('hide').append(one_button.html()+'<br/>');
});
disabled_button.on('click', function () {
disabled_button.attr('disabled', true);
setTimeout(function () {
result.removeClass('hide').append(disabled_button.html()+'<br/>');
}, 2000);
});

Although there are some good solutions offered, the method I ended up using was to just use a <button class="link"> that I can set the disabled attribute on.
Sometimes simplest solution is best.

You can disable click event on that link second time by using Jquery
$(this).unbind('click');
See this jsfiddle for reference
Demo

You can disable your links (for instance, href="#" ), and use a click event instead, binded to the link using the jQuery one() function.

Bind all the links with class "button" and try this:
$("a.button").click(function() { $(this).attr("disabled", "disabled"); });
$(document).click(function(evt) {
if ($(evt.target).is("a[disabled]"))
return false;
});

How to handle two unrelated events with jquery

I'm wondering if I can fire off both of these events together :
$("input[type=checkbox]").click(function(){
if($(this).is(":checked"))
{
//Value of checkbox
alert(this.value);
}
});
and
$("input[type= 'text']").keyup(function(){
alert(this.value);
});
I looked into .bind, but that seems to only work for one selected elements (i.e. $(p).bind("mouseout mouseenter).doSomething()).
The situation I am running into is that I have a function that needs to fire anytime either one of these things occur.

Try
$("input[type=checkbox],input[type='text']").on('click keyup', function(){
// code
});

Two ways you can achieve this as shown below:
using "on" method:
$(document).on('keyup click',"input[type=checkbox],input[type='text']", function(){
// Do stuff here..
})
Call function after the event.
$("input[type=checkbox]").click(doSomething);
$("input[type= 'text']").keyup(doSomething);
function doSomething() {
}

If you still need the additional if, you can use:
$("input[type=checkbox]").click(function(){
if($(this).is(":checked"))
{
//Value of checkbox
alert(this.value);
somethingHappened();
}
});
$("input[type= 'text']").keyup(function(){
alert(this.value);
somethingHappened();
});
function somethingHappened() {
// Do stuff
}

Perhaps all you need is a common function?
$("input[type=checkbox]").click(function(){
if($(this).is(":checked")) {
special(this.value);
}
});
$("input[type= 'text']").keyup(function(){
special(this.value);
});
function special(val) {
alert(val);
}

If your intent really is to invoke a function when any checkboxes/text fields across the whole page changes, you probably want something like this:
$('body').on('change', ':checkbox,:text', function () {
});
Note that the :checkbox and :text selectors are much nicer than input[type=checkbox] etc.