如何获取选定单选按钮的值？

Question

I want to get the selected value from a group of radio buttons.

Here's my HTML:

<div id="rates">
  <input type="radio" id="r1" name="rate" value="Fixed Rate"> Fixed Rate
  <input type="radio" id="r2" name="rate" value="Variable Rate"> Variable Rate
  <input type="radio" id="r3" name="rate" value="Multi Rate" checked="checked"> Multi Rate  
</div>

Here's my js:

var rates = document.getElementById('rates').value;
var rate_value;
if(rates =='Fixed Rate'){
    rate_value = document.getElementById('r1').value;
    
}else if(rates =='Variable Rate'){
    rate_value = document.getElementById('r2').value;
    
}else if(rates =='Multi Rate'){
    rate_value = document.getElementById('r3').value;
}  

document.getElementById('results').innerHTML = rate_value;

I keep getting undefined.

Answer 1

这适用于 IE9 及更高版本以及所有其他浏览器。

document.querySelector('input[name="rate"]:checked').value;

Answer 2

var rates = document.getElementById('rates').value;

The rates element is a div , so it won't have a value. This is probably where the undefined is coming from.

The checked property will tell you whether the element is selected:

if (document.getElementById('r1').checked) {
  rate_value = document.getElementById('r1').value;
}

Or

$("input[type='radio'][name='rate']:checked").val();

Answer 3

您可以使用checked<\/code>属性获取值。

var rates = document.getElementsByName('rate');
var rate_value;
for(var i = 0; i < rates.length; i++){
    if(rates[i].checked){
        rate_value = rates[i].value;
    }
}

Answer 4

For you people living on the edge:

There is now something called a RadioNodeList and accessing it's value property will return the value of the currently checked input. This will remove the necessity of first filtering out the 'checked' input as we see in many of the posted answers.

Example Form

<form id="test">
<label><input type="radio" name="test" value="A"> A</label>
<label><input type="radio" name="test" value="B" checked> B</label>
<label><input type="radio" name="test" value="C"> C</label>
</form>

To retrieve the checked value, you could do something like this:

var form = document.getElementById("test");
alert(form.elements["test"].value);

The JSFiddle to prove it: http://jsfiddle.net/vjop5xtq/

Please note this was implemented in Firefox 33 (All other major browser seems to support it). Older browsers will require a polfyill for RadioNodeList for this to properly function

Answer 5

The one worked for me is given below from api.jquery.com.

HTML

<input type="radio" name="option" value="o1">option1</input>
<input type="radio" name="option" value="o2">option2</input>

JavaScript

var selectedOption = $("input:radio[name=option]:checked").val()

The variable selectedOption will contain the value of the selected radio button (ie) o1 or o2

Answer 6

Another (apparently older) option is to use the format: "document.nameOfTheForm.nameOfTheInput.value;" eg document.mainForm.rads.value;

 document.mainForm.onclick = function(){ var radVal = document.mainForm.rads.value; result.innerHTML = 'You selected: '+radVal; }

 <form id="mainForm" name="mainForm"> <input type="radio" name="rads" value="1" /> <input type="radio" name="rads" value="2" /> <input type="radio" name="rads" value="3" /> <input type="radio" name="rads" value="4" /> </form> <span id="result"></span>

You can refer to the element by its name within a form. Your original HTML does not contain a form element though.

Fiddle here (works in Chrome and Firefox): https://jsfiddle.net/Josh_Shields/23kg3tf4/1/

Answer 7

Use document.querySelector('input[type = radio]:checked').value; to get value of selected checkbox , you can use other attributes to get value like name = gender etc. please go through below snippet definitely it will helpful to you,

Solution

 document.mainForm.onclick = function(){ var gender = document.querySelector('input[name = gender]:checked').value; result.innerHTML = 'You Gender: '+gender; }

 <form id="mainForm" name="mainForm"> <input type="radio" name="gender" value="Male" checked/>Male <input type="radio" name="gender" value="Female" />Female <input type="radio" name="gender" value="Others" />Others </form> <span id="result"></span>

Thank-You

Answer 8

HTML CODE:

<input type="radio" name="rdoName" value="YES"/> <input type="radio" name="rdoName" value="NO"/>

JQUERY CODE:

var value= $("input:radio[name=rdoName]:checked").val();

 $("#btnSubmit").click(function(){ var value=$("input:radio[name=rdoName]:checked").val(); console.log(value); alert(value); })

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <input type="radio" name="rdoName" value="YES"/> YES <input type="radio" name="rdoName" value="NO"/> NO <br/> <input type="button"id="btnSubmit"value="Which one Selected"/>

You will get

value="YES" //if checked Radio Button with the value "YES"
value="NO" //if checked Radio Button with the value "NO"

Answer 9

In Javascript we can get the values by using Id's " getElementById() " in the above code you posted has contain name not Id so you to modify like this

if (document.getElementById('r1').checked) {
  rate_value = document.getElementById('r1').value;
}

use this rate_value according to your code

Answer 10

A year or so has passed since the question was asked, but I thought a substantial improvement of the answers was possible. I find this the easiest and most versatile script, because it checks whether a button has been checked, and if so, what its value is:

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>Check radio checked and its value</title>
</head>
<body>

    <form name="theFormName">
        <input type="radio" name="theRadioGroupName" value="10">
        <input type="radio" name="theRadioGroupName" value="20">
        <input type="radio" name="theRadioGroupName" value="30">
        <input type="radio" name="theRadioGroupName" value="40">
        <input type="button" value="Check" onclick="getRadioValue('theRadioGroupName')">
    </form>

    <script>
        function getRadioValue(groupName) {
            var radios = theFormName.elements[groupName];
            window.rdValue; // declares the global variable 'rdValue'
            for (var i=0; i<radios.length; i++) {
                var someRadio = radios[i];
                if (someRadio.checked) {
                    rdValue = someRadio.value;
                    break;
                }
                else rdValue = 'noRadioChecked';
            }
            if (rdValue == '10') {
                alert('10'); // or: console.log('10')
            }
            else if (rdValue == 'noRadioChecked') {
                alert('no radio checked');
            }
        }
    </script>
</body>
</html>

You can also call the function within another function, like this:

function doSomething() {
    getRadioValue('theRadioGroupName');
    if (rdValue == '10') {
        // do something
    }
    else if (rdValue == 'noRadioChecked') {
        // do something else
    }  
} 

Answer 11

Assuming your form element is referred to by myForm variable below, and that your radio buttons share the name "my-radio-button-group-name", the following is pure JavaScript and standards compliant (although I have not checked it to be available everywhere):

myForm.elements.namedItem("my-radio-button-group-name").value

The above will yield the value of a checked (or selected, as it is also called) radio button element, if any, or null otherwise. The crux of the solution is the namedItem function which works with radio buttons specifically.

See HTMLFormElement.elements , HTMLFormControlsCollection.namedItem and especially RadioNodeList.value , as namedItem usually returns a RadioNodeList object.

I use MDN because it allows one to track standards compliance, at least to a large degree, and because it is easier to comprehend than many WhatWG and W3C publications.

Answer 12

Shortest

[...rates.children].find(c=>c.checked).value

 let v= [...rates.children].find(c=>c.checked).value console.log(v);

 <div id="rates"> <input type="radio" id="r1" name="rate" value="Fixed Rate"> Fixed Rate <input type="radio" id="r2" name="rate" value="Variable Rate"> Variable Rate <input type="radio" id="r3" name="rate" value="Multi Rate" checked="checked"> Multi Rate </div>

Answer 13

directly calling a radio button many times gives you the value of the FIRST button, not the CHECKED button. instead of looping thru radio buttons to see which one is checked, i prefer to call an onclick javascript function that sets a variable that can later be retrieved at will.

<input type="radio" onclick="handleClick(this)" name="reportContent" id="reportContent" value="/reportFleet.php" >

which calls:

var currentValue = 0;
function handleClick(myRadio) {
    currentValue = myRadio.value;
    document.getElementById("buttonSubmit").disabled = false; 
}

additional advantage being that i can treat data and/or react to the checking of a button (in this case, enabling SUBMIT button).

Answer 14

You can also loop through the buttons with a forEach-loop on the elements

    var elements = document.getElementsByName('radioButton');
    var checkedButton;
    console.log(elements);
    elements.forEach(e => {
        if (e.checked) {
            //if radio button is checked, set sort style
            checkedButton = e.value;
        }
    });

Answer 15

An improvement to the previous suggested functions:

function getRadioValue(groupName) {
    var _result;
    try {
        var o_radio_group = document.getElementsByName(groupName);
        for (var a = 0; a < o_radio_group.length; a++) {
            if (o_radio_group[a].checked) {
                _result = o_radio_group[a].value;
                break;
            }
        }
    } catch (e) { }
    return _result;
}

Answer 16

You can use .find() to select checked element:

var radio = Array.from(document.querySelectorAll('#rate input'))

var value = radio.length && radio.find(r => r.checked).value

Answer 17

My take on this problem with pure javascript is to find the checked node, find its value and pop it out from the array.

var Anodes = document.getElementsByName('A'),
    AValue = Array.from(Anodes)
       .filter(node => node.checked)
       .map(node => node.value)
       .pop();
console.log(AValue);

Note that I'm using arrow functions . See this fiddle for a working example.

Answer 18

如果您使用的是 jQuery：

$('input[name="rate"]:checked').val();

Answer 19

如果你使用没有 jQuery 的 javascript，你可以使用这个命令：

document.querySelector(`input[type="radio"][name=rate]:checked`).value

Answer 20

<form id="rates">
  <input type="radio" name="rate" value="Fixed Rate"> Fixed
  <input type="radio" name="rate" value="Variable Rate"> Variable
  <input type="radio" name="rate" value="Multi Rate" checked> Multi
</form>

then...

var rate_value = rates.rate.value;

Answer 21

按 ID 检查值：

var CheckedValues = ($("#r1").is(':checked')) ? 1 : 0;

Answer 22

I used the jQuery.click function to get the desired output:

$('input[name=rate]').click(function(){
  console.log('Hey you clicked this: ' + this.value);

  if(this.value == 'Fixed Rate'){
    rate_value = $('#r1').value;
  } else if(this.value =='Variable Rate'){
   rate_value = $('#r2').value;
  } else if(this.value =='Multi Rate'){
   rate_value = $('#r3').value;
  }  

  $('#results').innerHTML = rate_value;
});

Hope it helps.

Answer 23

If the buttons are in a form
var myform = new FormData(getformbywhatever); myform.get("rate");
QuerySelector above is a better solution. However, this method is easy to understand, especially if you don't have a clue about CSS. Plus, input fields are quite likely to be in a form anyway.
Didn't check, there are other similar solutions, sorry for the repetition

Answer 24

var rates = document.getElementById('rates').value;

无法获得这样的单选按钮的值，而是使用

rate_value = document.getElementById('r1').value;

Answer 25

如果您使用的是JQuery ，请使用下面的代码段作为单选按钮组。

var radioBtValue= $('input[type=radio][name=radiobt]:checked').val();

Answer 26

只需使用： document.querySelector('input[rate][checked]').value

Answer 27

Here is a solution putting the radio buttons in a constant and getting the selected value only when needed.

 const rates = document.forms.rates.elements["rate"] showRate() function showRate(){ document.getElementById('results').innerHTML = rates.value }

 <form id="rates" onchange="showRate()"> <input type="radio" id="r1" name="rate" value="Fixed Rate"> Fixed Rate <input type="radio" id="r2" name="rate" value="Variable Rate"> Variable Rate <input type="radio" id="r3" name="rate" value="Multi Rate" checked="checked"> Multi Rate </form> <div id="results"></div>

Answer 28

https://codepen.io/anon/pen/YQxbZJ

The HTML

<div id="rates">
<input type="radio" id="x1" name="rate" value="Fixed Rate"> Fixed Rate
<input type="radio" id="x2" name="rate" value="Variable Rate" 
checked="checked"> Variable Rate
<input type="radio" id="x3" name="rate" value="Multi Rate" > Multi Rate
</div>

<button id="rdio"> Check Radio </button>
<div id="check">

</div>

The JS

var x ,y;
var x = document.getElementById("check");
function boom()
{
if (document.getElementById("x1").checked)
  y = document.getElementById("x1").value;

else if(document.getElementById("x2").checked)
  y = document.getElementById("x2").value;

else if (document.getElementById("x3").checked)
  y = document.getElementById("x3").value;
else
  y = "kuch nhi;"
x.innerHTML = y;
}

var z = document.getElementById('rdio');
z.addEventListener("click", boom);`

Answer 29

 var rates=document.getElementsByName("rate"); for (i = 0; i < rates.length; i++) { if (rates[i].checked) { console.log(rates[i].value); rate=rates[i].value; document.getElementById("rate").innerHTML = rate; alert(rate); } }

 <div id="rates"> <input type="radio" id="r1" name="rate" value="Fixed Rate"> Fixed Rate <input type="radio" id="r2" name="rate" value="Variable Rate"> Variable Rate <input type="radio" id="r3" name="rate" value="Multi Rate" checked="checked"> Multi Rate </div> </br> <div id='rate'> </div>

Answer 30

In php it's very easy
html page

 Male<input type="radio" name="radio" value="male"><br/> Female<input type="radio" name="radio" value="female"><br/> Others<input type="radio" name="radio" value="other"><br/> <input type="submit" value="submit">

Take value from form to php

$radio=$_POST['radio'];<br/>
use php if(isset($_POST['submit']))<br/>
{<br/>
echo "you selected".$radio."thank u";<br/>
}