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Set checkbox to be checked if input value =

I have an input and a checkbox. I have managed to change the value in the input on clicking the checkbox, and un clicking etc which works fine.
I'm looking to auto set the checkbox to be checked on page load only if the input value = yes, as this input value is being loaded dynamically via php and may not be yes.
HTML
<input type="text" value = "yes" id ="inputId">
<input type="checkbox" id = "yourCheckboxId">
JQUERY
$('#yourCheckboxId').click(function() {
if ($('#yourCheckboxId').is(':checked')){
$('#inputId').val('yes');
}
if (!$('#yourCheckboxId').is(':checked')){
$('#inputId').val('no');
}
});
You'll notice that even though the value in the input is set to yes, on page load, the checkbox isn't checked. This is what I have so far, see jsfiddle here: http://jsfiddle.net/0z9agrw8/1/
Thanks

var input = $('#inputId').val()
if(input === "yes"){
$("#yourCheckboxId").prop('checked', true);
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" value = "yes" id ="inputId">
<input type="checkbox" id = "yourCheckboxId">

Do this on page load:
if($('#inputId').val() == 'yes') {
$('#yourCheckboxId').prop('checked', true);
}

If you always want it to be checked on page load, you can simply add the "checked" attribute
eg
<input type="checkbox" id = "yourCheckboxId" checked>
If it's more complicated than that, the other answers will work nicely

check checkbox if another checkbox is checked

I want the checkbox with the value 2 to automatically get checked if the checkbox with the value 1 is checked. Both have the same id so I can't use getElementById.
html:
<input type="checkbox" value="1" id="user_name">1<br>
<input type="checkbox" value="2" id="user_name">2
I tired:
var chk1 = $("input[type="checkbox"][value="1"]");
var chk2 = $("input[type="checkbox"][value="2"]");
if (chk1:checked)
chk2.checked = true;

You need to change your HTML and jQuery to this:
var chk1 = $("input[type='checkbox'][value='1']");
var chk2 = $("input[type='checkbox'][value='2']");
chk1.on('change', function(){
chk2.prop('checked',this.checked);
});
id is unique, you should use class instead.
Your selector for chk1 and chk2 is wrong, concatenate it properly using ' like above.
Use change() function to detect when first checkbox checked or unchecked then change the checked state for second checkbox using prop().
Fiddle Demo

Id should be unique, so that set different ids to your elements, By the way you have to use .change() event to achieve what you want.
Try,
HTML:
<input type="checkbox" value="1" id="user_name1">1<br>
<input type="checkbox" value="2" id="user_name2">2
JS:
var chk1 = $("input[type='checkbox'][value='1']");
var chk2 = $("input[type='checkbox'][value='2']");
chk1.change(function(){
chk2.prop('checked',this.checked);
});

You need to change the ID of one. It is not allowed by W3C standard (hence classes vs ID's). jQuery will only process the first ID, but most major browsers will treat ID's similar to classes since they know developers mess up.
Solution:
<input type="checkbox" value="1" id="user_name">1<br>
<input type="checkbox" value="2" id="user_name_2">2
With this JS:
var chk1 = $('#user_name');
var chk2 = $('#user_name2');
//check the other box
chk1.on('click', function(){
if( chk1.is(':checked') ) {
chk2.attr('checked', true);
} else {
chk2.attr('checked', false);
}
});
For more information on why it's bad to use ID's see this: Why is it a bad thing to have multiple HTML elements with the same id attribute?

The error is probably coming here "input[type="checkbox"]
Here your checkbox is out of the quotes, so you query is looking for input[type=][value=1]
Change it to "input[type='checkbox'] (Use single quote inside double quote, though you don't need to quote checkbox)
http://api.jquery.com/checked-selector/

first create an input type checkbox:
<input type='checkbox' id='select_all'/>
$('#select_all').click(function(event) {
if(this.checked) {
$(':checkbox').each(function() {
this.checked = true;
});
}
});

How can I toggle radiobutton

Say this is my HTML:
<input type="radio" name="rad" id="Radio0" checked="checked" />
<input type="radio" name="rad" id="Radio1" />
<input type="radio" name="rad" id="Radio2" />
<input type="radio" name="rad" id="Radio4" />
<input type="radio" name="rad" id="Radio3" />
As you can see the 1st radio button is checked. I need the radio button to function like toggle. For eg. If I again click on radio0, all radio buttons should be unchecked.
How can I achieve that?
Update: I don't want any extra buttons. For eg. I could add a button and set the checked property for all radio buttons to be false. However, I don't want that. I only want my form to consist of these 4 radio buttons.
Update: Since most of the people don't understand what I want, let me try to rephrase- I want the radio button to function in toggle mode. I've given the same name to all radio buttons hence it's a group. Now I want the radiobuttons to toggle itself. Eg. if I click on radio0, it should get unchecked if it's checked and checked if it's unchecked.

The problem you'll find is that as soon a radio button is clicked its state is changed before you can check it. What I suggest is to add a custom attribute to keep track of each radio's previous state like so:
$(function(){
$('input[name="rad"]').click(function(){
var $radio = $(this);
// if this was previously checked
if ($radio.data('waschecked') == true)
{
$radio.prop('checked', false);
$radio.data('waschecked', false);
}
else
$radio.data('waschecked', true);
// remove was checked from other radios
$radio.siblings('input[name="rad"]').data('waschecked', false);
});
});
You will also need to add this attribute to the initially checked radio markup
<input type="radio" name="rad" id="Radio0" checked="checked" data-waschecked="true" />
See demo here : http://jsfiddle.net/GoranMottram/VGPhD/2/

Once you give the name of 2 or more radio buttons as the same, they automatically become a group. In that group only one radio button can be checked. You have already achieved this.

This code solved my issue
$("[type='radio']").on('click', function (e) {
var previousValue = $(this).attr('previousValue');
if (previousValue == 'true') {
this.checked = false;
$(this).attr('previousValue', this.checked);
}
else {
this.checked = true;
$(this).attr('previousValue', this.checked);
}
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<label >Toogle radio button example</label>
<br />
<input type="radio" name="toogle_me" value="mango"> Blue </input>
<input type="radio" name="toogle_me" value="kiwi"> Green </input>
<input type="radio" name="toogle_me" value="banana"> Yellow </input>
<input type="radio" name="toogle_me" value="orange"> Orange </input>

I use an onClick() like the following for my custom radios:
$(function(){
// if selected already, deselect
if ($(this).hasClass('selected') {
$(this).prop('checked', false);
$(this).removeClass('selected');
}
// else select
else {
$(this).prop('checked', true);
$(this).addClass('selected');
}
// deselect sibling inputs
$(this).siblings('input').prop('checked', false);
$(this).siblings('input').removeClass('selected');
}

Using #Goran Mottram answer just tweaking it a bit to suit the case where radio buttons are not siblings.
$(".accordian-radio-button").click(function(){
var wasChecked = true;
if($(this).data('waschecked') == true){
$(this).prop('checked', false);
wasChecked = false;
}
$('input[name="ac"]').data('waschecked', false);
$(this).data('waschecked', wasChecked);
})
<input class="accordian-radio-button" data-waschecked="false" type="radio" name="ac" id="a1" />

I ran into this as well, after thinking about it and playing around with the various fiddles offered, I had a few dissatisfactions with the offered solutions.
My main problem was the last line of the accepted answer, requiring a reset:
// remove was checked from other radios
$radio.siblings('input[name="rad"]').data('waschecked', false);
And since I'm not using jQuery, I'd have to loop over and evaluate the siblings myself, which isn't a huge deal, but seemed inelegant to me. But, there's no way around it with that method, because you're using the dataset as a storage of information.
After playing around, I realized is that the problem is that when a radio is clicked, it triggers the clicked event, and whatever function is attached to that click event completes itself before the function for the "onchange" event is ever evaluated, let alone called. So, if the click event "unchecks" the toggle, then no change event is ever fired.
I've left my failed attempt here:
https://codepen.io/RiverRockMedical/pen/daMGVJ
But, if you could answer the question "will a change event happen after this click event?" then you could get a toggle working.
The solution I came up with can be seen at this pen:
https://codepen.io/RiverRockMedical/pen/VgvdrY
But basically is as follows:
function onClick(e) {
e.dataset.toDo = 'uncheck';
setTimeout(uncheck, 1, {
event:'click',
id:e.id,
dataset:e.dataset
});
}
So, on the click event, set a marker that the click has happened, and the use setTimeout() to create a pause that allows the onchange event to be evaluated and fire.
function onChange(e) {
e.dataset.toDo = 'leave';
}
If the onchange event fires, it undoes what was done by the onclick event.
function uncheck(radio) {
log('|');
if (radio.event !== 'click') return;
log('uncheck');
if (radio.dataset.toDo === 'uncheck') {
document.getElementById(radio.id).checked = false;
radio.checked = false;
}
}
Then, when the uncheck function starts, it has the information of whether a change event followed the click event or not. If not, then the radio is unchecked, and functions as a toggle.
And, it's basically self-resetting, so I don't have to loop over all the radios and reset their datasets to the initial values at the end of the function.
Now, I'm sure there's a cooler async/await way to do this that doesn't use setTimeout and would be even more elegant, but I'm still learning and I couldn't come up with it. Anyone else?

<input type="radio" name="gender" id="male"onclick="getChecked(1)"><label for="male">Male</label>
<input type="radio" name="gender" id="female"onclick="getChecked(2)"><label for="female">female</label>
<script>
var btnChecked = "";
function getChecked(i) {
if(btnChecked == i) {
btnChecked = "";
document.getElementsByTagName("input")[i-1].checked = false;
}
else btnChecked = i;
}
</script>

A simple approach in jQuery (even though I don't use jQuery nowdays):
function makeRadioInputsToggleable(radioInputs){
let radioGroup = {
lastValue: radioInputs.filter(':checked').prop('value'),
get value(){
return this.lastValue;
},
set value(v){
let inputToCheck = radioInputs.filter((i, el) => el.value === v);
radioInputs.filter(':checked').prop('checked', false);
if(inputToCheck.length > 0){
inputToCheck.prop('checked', true);
this.lastValue = v;
}else{
this.lastValue = undefined;
}
},
};
radioInputs.on('click', (e) => {
let input = e.target;
if(input.value === radioGroup.lastValue){
input.checked = false;
radioGroup.lastValue = undefined;
}else{
radioGroup.lastValue = input.value;
}
}).on('keydown', (e) => {
if(e.code === 'Space'){
let input = e.target;
if(input.checked){
input.checked = false;
input.blur();
radioGroup.lastValue = undefined;
}
}
});
return radioGroup;
}
let radioInputs = $('input[type="radio"][name="rad"]');
let radioGroup = makeRadioInputsToggleable(radioInputs);
$('.check-radio').on('click', (e)=>{
let value = e.target.value;
radioGroup.value = value;
});
// Note:
// 1. pass a single group of radio inputs to `makeRadioInputsToggleable`
// 2. set distinct values for each radio input in a group.
// 3. to change checked radio programmatically, use `radioGroup.value = 'XXX'` rather than radioInputs.prop('checked', false).filter('[value="XXX"]').prop('checked', true);
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<h3>makeRadioInputsToggleable</h3>
<label><input type="radio" name="rad" value="1" id="Radio0" checked="checked" />1</label>
<label><input type="radio" name="rad" value="2" id="Radio1" />2</label>
<label><input type="radio" name="rad" value="3" id="Radio2" />3</label>
<label><input type="radio" name="rad" value="4" id="Radio4" />4</label>
<label><input type="radio" name="rad" value="5" id="Radio3" />5</label>
<p>1. click on an already-checked radio button, the radio will be toggled to unchecked.</p>
<p>2. focus on an already-checked radio button and press 'Space', the radio will be toggled to unchecked. <i>(This may not work in Code Snippet result area)</i></p>
<p>
3. programmatically
<button class="check-radio" value="2">check radio with value 2</button>
<button class="check-radio" value="10">check radio with value 10</button>
</p>

How to check radio button is checked using JQuery?

I have two radio buttons in one group, I want to check the radio button is checked or not using JQuery, How ?

Given a group of radio buttons:
<input type="radio" id="radio1" name="radioGroup" value="1">
<input type="radio" id="radio2" name="radioGroup" value="2">
You can test whether a specific one is checked using jQuery as follows:
if ($("#radio1").prop("checked")) {
// do something
}
// OR
if ($("#radio1").is(":checked")) {
// do something
}
// OR if you don't have ids set you can go by group name and value
// (basically you need a selector that lets you specify the particular input)
if ($("input[name='radioGroup'][value='1']").prop("checked"))
You can get the value of the currently checked one in the group as follows:
$("input[name='radioGroup']:checked").val()

//the following code checks if your radio button having name like 'yourRadioName'
//is checked or not
$(document).ready(function() {
if($("input:radio[name='yourRadioName']").is(":checked")) {
//its checked
}
});

This is best practice
$("input[name='radioGroup']:checked").val()

jQuery 3.3.1
if (typeof $("input[name='yourRadioName']:checked").val() === "undefined") {
alert('is not selected');
}else{
alert('is selected');
}

Radio buttons are,
<input type="radio" id="radio_1" class="radioButtons" name="radioButton" value="1">
<input type="radio" id="radio_2" class="radioButtons" name="radioButton" value="2">
to check on click,
$('.radioButtons').click(function(){
if($("#radio_1")[0].checked){
//logic here
}
});

Check this one out, too:
$(document).ready(function() {
if($("input:radio[name='yourRadioGroupName'][value='yourvalue']").is(":checked")) {
//its checked
}
});

Taking some answers one step further - if you do the following you can check if any element within the radio group has been checked:
if ($('input[name="yourRadioNames"]:checked').val()){ (checked) or if (!$('input[name="yourRadioNames"]:checked').val()){ (not checked)

Try this:
var count =0;
$('input[name="radioGroup"]').each(function(){
if (this.checked)
{
count++;
}
});
If any of radio button checked than you will get 1

Simply you can check the property.
if( $("input[name='radioButtonName']").prop('checked') ){
//implement your logic
}else{
//do something else as radio not checked
}

JS / JQuery - Check All Checkboxes

I have a photo gallery. Underneath each photo is a checkbox, with the ID containing a prefix of 'checkbox_', followed by the photo ID.
<input type="checkbox" id="checkbox_<%=photoID%>" name="photos">
When I check a 'selectAll' checkbox, like this one:
<input type="checkbox" id="toggleAll" name="toggleAll" onclick="toggleAll()">
I want to check/uncheck all checkboxes that have the name 'photos', so I have this function that should do that... but it doesn't:
function toggleAll() {
if (document.getElementById('toggleAll').checked == true)
{
$('.photoBlob').animate({backgroundColor: 'rgba(0,102,204,0.5)'}, 500);
$('.photoBlob').animate({backgroundColor: 'rgba(204,204,204,1)'}, 1500);
document.getElementByName('photos').checked = true;
}
else
{
$('.photoBlob').animate({backgroundColor: 'rgba(0,0,0,0)'}, 1000);
document.getElementByName('photos').checked = false;
}
}
The rest of the function works okay, it animates the background colors of the containing DIV (#photoBlob) when the toggleALL() function is called. But, I really can't get all the checkboxes to check and I have tried so many different variations!
Can anybody see what I am doing wrong? The problem lies with these two lines:
document.getElementByName('photos').checked = true;
document.getElementByName('photos').checked = false;
Any suggestions gratefully received...

You can do like this,
don't use same name for several check boxes because the name shroud be unique. Instead of use the class.
<input type="checkbox" id="checkbox_<%=photoID%>" class="photos">
an the jquery,
$('#toggleAll').click(function(){
var checked =$(this).attr('checked');
$('.photos').attr('checked', checked);
}

$('#toggleAll').click(function(){
$(':checkbox[name="photos"]').prop('checked',this.checked);
});
Fiddle demo: http://jsfiddle.net/uNeX2/

I think you're missing an "s" in getElementByTagName. Try getElementsByTagName.
This might also work:
$("#toggleAll").click(function() {<br/>
$("input[name='photos']").attr("checked",!!$(this).attr("checked"));
});

well, since you said, you have multiple checkboxes with the name 'photos', selecting only one element by using the function getElementByName, can't be ur choice of game. Using jQuery simplifies the task your trying to do;
$("input[name=photos]").each(function(elem){
elem.checked=true;
}
or simpler;
$("input[name=photos]").attr('checked','checked');
its its js-only, youd need to select all input elements via getElementsByTagName and then filter out the ones that don't comply with having a name of 'photos'.. and then do your task.

Here is simple example using jQuery:
html
<input type="checkbox" id="all" >
<input type="checkbox" name="photo" >
<input type="checkbox" name="photo" >
<input type="checkbox" name="photo" >
<input type="checkbox" name="photo" >
js
$('#all').click(function() {
if ($(this).attr('checked') == undefined) {
$('input[name=photo]').removeAttr('checked');
}
else {
$('input[name=photo]').attr('checked', 'checked');
}
});
Code: http://jsfiddle.net/b8Y9t/3/

I would use:
$('.photos:checkbox').attr('checked','checked');

There is no function called getElementByName. Did you have a javascript-error? I think it should be getElementsByName. This returns a list with elements. That means you have to loop trough it to check all checkboxes.
BTW I think it is not correct to use a name called 'photos' for a checkbox, since a checkbox is a single object and does not display a photo itself. I would name it 'photoCheckbox' or 'cbPhoto' to clearify it is a checkbox.
var checkboxList = getElementsByName('photoCheckbox'); // returns list with checkboxes with name 'photoCheckbox'
if (checkboxList)
{
for (var i = 0; i < checkboxList.length; i++)
{
var checkbox = checkboxList[i];
checkbox.checked = false;
}
}
Thats how the getElementsByName function works. So if you would evaluate this method, you would say this is unnecessary since you are already using jQuery? I would simplify the code of the checkbox:
<input type="checkbox" onclick="toggleAll(this)" />
The new toggleAll function looks like this:
function toggleAll(checkbox)
{
if (checkbox.checked)
{
$('.photoBlob').animate({backgroundColor: 'rgba(0,102,204,0.5)'}, 500);
$('.photoBlob').animate({backgroundColor: 'rgba(204,204,204,1)'}, 1500); // btw why 2 animations on the same elements..?
$('input[name="photos"]').prop("checked", true);
}
else
{
$('.photoBlob').animate({backgroundColor: 'rgba(0,0,0,0)'}, 1000);
$('input[name="photos"]').prop("checked", false);
}
}

// jquery check all or uncheck all
$('.checkall').click(function(){
var status = 'false';
status = $('.checkall').is(":checked");
//alert ('status is ' + status); // you should see true or false
$('.metacheckbox').each( function() {
$(this).attr('checked', status);
});
});
<input class="checkall" type="checkbox" />Check/UnCheck All
<input class="metacheckbox" type="checkbox" id='checkboxone' name="checkboxone" value="Y" />
<input class="metacheckbox" type="checkbox" id='checkboxtwo' name="checkboxtwo" value="Y" />
<input class="metacheckbox" type="checkbox" id='checkboxthree' name="checkboxthree" value="Y" />
this worked for me.