I have two radio buttons within an HTML form. A dialog box appears when one of the fields is null. How can I check whether a radio button is selected?
29 Answers
Let's pretend you have HTML like this
<input type="radio" name="gender" id="gender_Male" value="Male" /> <input type="radio" name="gender" id="gender_Female" value="Female" /> For client-side validation, here's some Javascript to check which one is selected:
if(document.getElementById('gender_Male').checked) { //Male radio button is checked }else if(document.getElementById('gender_Female').checked) { //Female radio button is checked } The above could be made more efficient depending on the exact nature of your markup but that should be enough to get you started.
If you're just looking to see if any radio button is selected anywhere on the page, PrototypeJS makes it very easy.
Here's a function that will return true if at least one radio button is selected somewhere on the page. Again, this might need to be tweaked depending on your specific HTML.
function atLeastOneRadio() { return ($('input[type=radio]:checked').size() > 0); } For server-side validation (remember, you can't depend entirely on Javascript for validation!), it would depend on your language of choice, but you'd but checking the gender value of the request string.
8 Comments
With jQuery, it'd be something like
if ($('input[name=gender]:checked').length > 0) { // do something here } Let me break that down into pieces to cover it more clearly. jQuery processes things from left to right.
input[name=gender]:checked inputlimits it to input tags.[name=gender]limits it to tags with the name gender within the previous group.:checkedlimits it to checkboxes/radio buttons that are selected within the previous group.
If you want to avoid this altogether, mark one of the radio buttons as checked (checked="checked") in the HTML code, which would guarantee that one radio button is always selected.
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A vanilla JavaScript way
var radios = document.getElementsByTagName('input'); var value; for (var i = 0; i < radios.length; i++) { if (radios[i].type === 'radio' && radios[i].checked) { // get value, set checked flag or do whatever you need to value = radios[i].value; } } 7 Comments
name.You can use this simple script. You may have multiple radio buttons with same names and different values.
var checked_gender = document.querySelector('input[name = "gender"]:checked'); if(checked_gender != null){ //Test if something was checked alert(checked_gender.value); //Alert the value of the checked. } else { alert('Nothing checked'); //Alert, nothing was checked. } 3 Comments
document.forms[0].elements['nameOfRadioList'].valuequerySelector not querySelectorAll. I kept getting undefined....... :-)Just trying to improve on Russ Cam's solution with some CSS selector sugar thrown in with the vanilla JavaScript.
var radios = document.querySelectorAll('input[type="radio"]:checked'); var value = radios.length>0? radios[0].value: null; No real need for jQuery here, querySelectorAll is widely supported enough now.
Edit: fixed a bug with the css selector, I've included the quotes, although you can omit them, in some cases you can't so it's better to leave them in.
3 Comments
a[href^="http://"]) they would be required, and consistency is more maintainable. Besides, this lets the attribute declaration match the corresponding HTML.HTML Code
<input type="radio" name="offline_payment_method" value="Cheque" > <input type="radio" name="offline_payment_method" value="Wire Transfer" > Javascript Code:
var off_payment_method = document.getElementsByName('offline_payment_method'); var ischecked_method = false; for ( var i = 0; i < off_payment_method.length; i++) { if(off_payment_method[i].checked) { ischecked_method = true; break; } } if(!ischecked_method) { //payment method button is not checked alert("Please choose Offline Payment Method"); } 1 Comment
I used spread operator and some to check least one element in the array passes the test.
I share for whom concern.
var checked = [...document.getElementsByName("gender")].some(c=>c.checked); console.log(checked); <input type="radio" name="gender" checked value="Male" /> Male <input type="radio" name="gender" value="Female" / > Female 1 Comment
The scripts in this page helped me come up with the script below, which I think is more complete and universal. Basically it will validate any number of radio buttons in a form, meaning that it will make sure that a radio option has been selected for each one of the different radio groups within the form. e.g in the test form below:
<form id="FormID"> Yes <input type="radio" name="test1" value="Yes"> No <input type="radio" name="test1" value="No"> <br><br> Yes <input type="radio" name="test2" value="Yes"> No <input type="radio" name="test2" value="No"> <input type="submit" onclick="return RadioValidator();"> The RadioValidator script will make sure that an answer has been given for both 'test1' and 'test2' before it submits. You can have as many radio groups in the form, and it will ignore any other form elements. All missing radio answers will show inside a single alert popup. Here it goes, I hope it helps people. Any bug fixings or helpful modifications welcome :)
<SCRIPT LANGUAGE="JAVASCRIPT"> function RadioValidator() { var ShowAlert = ''; var AllFormElements = window.document.getElementById("FormID").elements; for (i = 0; i < AllFormElements.length; i++) { if (AllFormElements[i].type == 'radio') { var ThisRadio = AllFormElements[i].name; var ThisChecked = 'No'; var AllRadioOptions = document.getElementsByName(ThisRadio); for (x = 0; x < AllRadioOptions.length; x++) { if (AllRadioOptions[x].checked && ThisChecked == 'No') { ThisChecked = 'Yes'; break; } } var AlreadySearched = ShowAlert.indexOf(ThisRadio); if (ThisChecked == 'No' && AlreadySearched == -1) { ShowAlert = ShowAlert + ThisRadio + ' radio button must be answered\n'; } } } if (ShowAlert != '') { alert(ShowAlert); return false; } else { return true; } } </SCRIPT> Comments
With mootools (http://mootools.net/docs/core/Element/Element)
html:
<input type="radio" name="radiosname" value="1" /> <input type="radio" name="radiosname" value="2" id="radiowithval2"/> <input type="radio" name="radiosname" value="3" /> js:
// Check if second radio is selected (by id) if ($('radiowithval2').get("checked")) // Check if third radio is selected (by name and value) if ($$('input[name=radiosname][value=3]:checked').length == 1) // Check if something in radio group is choosen if ($$('input[name=radiosname]:checked').length > 0) // Set second button selected (by id) $("radiowithval2").set("checked", true) 1 Comment
Note this behavior wit jQuery when getting radio input values:
$('input[name="myRadio"]').change(function(e) { // Select the radio input group // This returns the value of the checked radio button // which triggered the event. console.log( $(this).val() ); // but this will return the first radio button's value, // regardless of checked state of the radio group. console.log( $('input[name="myRadio"]').val() ); }); So $('input[name="myRadio"]').val() does not return the checked value of the radio input, as you might expect -- it returns the first radio button's value.
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There is very sophisticated way you can validate whether any of the radio buttons are checked with ECMA6 and method .some().
Html:
<input type="radio" name="status" id="marriedId" value="Married" /> <input type="radio" name="status" id="divorcedId" value="Divorced" /> And javascript:
let htmlNodes = document.getElementsByName('status'); let radioButtonsArray = Array.from(htmlNodes); let isAnyRadioButtonChecked = radioButtonsArray.some(element => element.checked); isAnyRadioButtonChecked will be true if some of the radio buttons are checked and false if neither of them are checked.
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this is a utility function I've created to solve this problem
//define radio buttons, each with a common 'name' and distinct 'id'. // eg- <input type="radio" name="storageGroup" id="localStorage"> // <input type="radio" name="storageGroup" id="sessionStorage"> //param-sGroupName: 'name' of the group. eg- "storageGroup" //return: 'id' of the checked radioButton. eg- "localStorage" //return: can be 'undefined'- be sure to check for that function checkedRadioBtn(sGroupName) { var group = document.getElementsByName(sGroupName); for ( var i = 0; i < group.length; i++) { if (group.item(i).checked) { return group.item(i).id; } else if (group[0].type !== 'radio') { //if you find any in the group not a radio button return null return null; } } } 1 Comment
This would be valid for radio buttons sharing the same name, no JQuery needed.
var x = Array.prototype.filter.call(document.getElementsByName('checkThing'), function(x) { return x.checked })[0]; If we are talking about checkboxes and we want a list with the checkboxes checked sharing a name:
var x = Array.prototype.filter.call(document.getElementsByName('checkThing'), function(x) { return x.checked }); Comments
With JQuery, another way to check the current status of the radio buttons is to get the attribute 'checked'.
For Example:
<input type="radio" name="gender_male" value="Male" /> <input type="radio" name="gender_female" value="Female" /> In this case you can check the buttons using:
if ($("#gender_male").attr("checked") == true) { ... } 1 Comment
$("#gender_male").attr("checked") is a string "checked" and not a boolean.just a lil bit modification to Mark Biek ;
HTML CODE
<form name="frm1" action="" method="post"> <input type="radio" name="gender" id="gender_Male" value="Male" /> <input type="radio" name="gender" id="gender_Female" value="Female" / > <input type="button" value="test" onclick="check1();"/> </form> and Javascript code to check if radio button is selected
<script type="text/javascript"> function check1() { var radio_check_val = ""; for (i = 0; i < document.getElementsByName('gender').length; i++) { if (document.getElementsByName('gender')[i].checked) { alert("this radio button was clicked: " + document.getElementsByName('gender')[i].value); radio_check_val = document.getElementsByName('gender')[i].value; } } if (radio_check_val === "") { alert("please select radio button"); } } </script> Comments
Try
[...myForm.sex].filter(r=>r.checked)[0].value function check() { let v= ([...myForm.sex].filter(r=>r.checked)[0] || {}).value ; console.log(v); } <form id="myForm"> <input name="sex" type="radio" value="men"> Men <input name="sex" type="radio" value="woman"> Woman </form> <br><button onClick="check()">Check</button> 1 Comment
So basically, what this code does is to loop through a nodeList that contains all the input elements. In case one of these input elements is of type radio and is checked then do something and break the loop.
If the loop doesn't detect an input element been selected, the boolean variable selected will stay false, and applying a conditional statement we can execute something for this case.
let inputs = document.querySelectorAll('input') let btn = document.getElementById('btn') let selected = false function check(){ for(const input of inputs){ if(input.type === 'radio' && input.checked){ console.log(`selected: ${input.value}`) selected = true break } } if(!selected) console.log(`no selection`) } btn.addEventListener('click', check) <input type="radio" name="option" value="one"> <label>one</label> <br> <input type="radio" name="option" value="two"> <label>two</label> <br> <br> <button id="btn">check selection</button> Comments
http://www.somacon.com/p143.php/
function getCheckedValue(radioObj) { if(!radioObj) return ""; var radioLength = radioObj.length; if(radioLength == undefined) if(radioObj.checked) return radioObj.value; else return ""; for(var i = 0; i < radioLength; i++) { if(radioObj[i].checked) { return radioObj[i].value; } } return ""; } Comments
I just want to ensure something gets selected (using jQuery):
// html <input name="gender" type="radio" value="M" /> Male <input name="gender" type="radio" value="F" /> Female // gender (required) var gender_check = $('input:radio[name=gender]:checked').val(); if ( !gender_check ) { alert("Please select your gender."); return false; } Comments
This code will alert the selected radio button when the form is submitted. It used jQuery to get the selected value.
$("form").submit(function(e) { e.preventDefault(); $this = $(this); var value = $this.find('input:radio[name=COLOR]:checked').val(); alert(value); }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <form> <input name="COLOR" id="Rojo" type="radio" value="red"> <input name="COLOR" id="Azul" type="radio" value="blue"> <input name="COLOR" id="Amarillo" type="radio" value="yellow"> <br> <input type="submit" value="Submit"> </form> Comments
HTML:
<label class="block"><input type="radio" name="calculation" value="add">+</label> <label class="block"><input type="radio" name="calculation" value="sub">-</label> <label class="block"><input type="radio" name="calculation" value="mul">*</label> <label class="block"><input type="radio" name="calculation" value="div">/</label> <p id="result"></p> JAVAScript:
var options = document.getElementsByName("calculation"); for (var i = 0; i < options.length; i++) { if (options[i].checked) { // do whatever you want with the checked radio var calc = options[i].value; } } if(typeof calc == "undefined"){ document.getElementById("result").innerHTML = " select the operation you want to perform"; return false; } Comments
Here is the solution which is expanded upon to not go ahead with submission and send an alert if the radio buttons are not checked. Of course this would mean you have to have them unchecked to begin with!
if(document.getElementById('radio1').checked) { } else if(document.getElementById('radio2').checked) { } else { alert ("You must select a button"); return false; } Just remember to set the id ('radio1','radio2' or whatever you called it) in the form for each of the radio buttons or the script will not work.
1 Comment
if (!document.getElementById('radio1').checked && !document.getElementById('radio2').checked) { alert(); }.An example:
if (!checkRadioArray(document.ExamEntry.level)) { msg+="What is your level of entry? \n"; document.getElementById('entry').style.color="red"; result = false; } if(msg==""){ return result; } else{ alert(msg) return result; } function Radio() { var level = radio.value; alert("Your level is: " + level + " \nIf this is not the level your taking then please choose another.") } function checkRadioArray(radioButtons) { for(var r=0;r < radioButtons.length; r++) { if (radioButtons[r].checked) { return true; } } return false; } Comments
The form
<form name="teenageMutant"> <input type="radio" name="ninjaTurtles"/> </form> The script
if(!document.teenageMutant.ninjaTurtles.checked){ alert('get down'); } The fiddle: http://jsfiddle.net/PNpUS/
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If you want vanilla JavaScript, don't want to clutter your markup by adding IDs on each radio button, and only care about modern browsers, the following functional approach is a little more tasteful to me than a for loop:
<form id="myForm"> <label>Who will be left? <label><input type="radio" name="output" value="knight" />Kurgan</label> <label><input type="radio" name="output" value="highlander" checked />Connor</label> </label> </form> <script> function getSelectedRadioValue (formElement, radioName) { return ([].slice.call(formElement[radioName]).filter(function (radio) { return radio.checked; }).pop() || {}).value; } var formEl = document.getElementById('myForm'); alert( getSelectedRadioValue(formEl, 'output') // 'highlander' ) </script> If neither is checked, it will return undefined (though you could change the line above to return something else, e.g., to get false returned, you could change the relevant line above to: }).pop() || {value:false}).value;).
There is also the forward-looking polyfill approach since the RadioNodeList interface should make it easy to just use a value property on the list of form child radio elements (found in the above code as formElement[radioName]), but that has its own problems: How to polyfill RadioNodeList?
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This might be helpful as well. It will return the input element that is currently selected.
const inputs = document.querySelectorAll('input.my-class'); const selectedInput = Array.from(inputs).find(input => input.checked); console.log(selectedInput.value) <input type="radio" class="my-class" value="one-time" > <input type="radio" class="my-class" value="subscription" checked="checked"> Comments
Give radio buttons, same name but different IDs.
var verified1 = $('#SOME_ELEMENT1').val(); var verified2 = $('#SOME_ELEMENT2').val(); var final_answer = null; if( $('#SOME_ELEMENT1').attr('checked') == 'checked' ){ //condition final_answer = verified1; } else { if($('#SOME_ELEMENT2').attr('checked') == 'checked'){ //condition final_answer = verified2; } else { return false; } }