如何获取选定的单选按钮值？

Question

I need get the selected radio button values. Radio button name is is_external

test.html

<div class="exter_inter">
    External <input type="radio" name="is_external" value="1" <?php if(isset($_GET['status']) && $_GET['status']=='1') echo "checked";?> />
    Internal <input type="radio" name="is_external" value="0"  <?php if(isset($_GET['status']) && $_GET['status']=='0') echo "checked";?>  />
</div>

script.js

$(document).ready(function() {  
    $('input:radio').change(function() {      
        var is_external = $("input[name='radio']:checked").val();   
        alert("selected values: " + is_external); //Return undefined  

    });
} ); 

Answer 1

 $(document).ready(function() { $('input:radio').change(function() { var is_external = $("input[name='is_external']:checked").val();//name is is_external not radio alert("selected values: " + is_external); //Return undefined }); }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div class="exter_inter"> External <input type="radio" name="is_external" value="1" />Internal <input type="radio" name="is_external" value="0" /> </div> 

Name is is_external not radio

Answer 2

   <input type="radio" name="user" value="newUser">New User
   <input type="radio" name="user" value="registeredUser">Registered User

    $(document).ready(function () {
        $("input:radio").change(function () {
            var x = $("input[name='user']:checked").val();
            console.log(x);
         });
    });