how to check if a radio button is checked code example

Example 1: check if radio button is checked

$('#element').click(function() {
   if($('#radio_button').is(':checked')) { alert("it's checked"); }
});

Example 2: html radio button checked

<input type="radio" id="huey" name="drone" value="huey"
         checked> 
<!-- https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/radio-->

Example 3: javascript radio button value if checked

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

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

if($test="silver") {
        amount=50;
    }else if($test="gold") {
      amount=90;
    }else{
      amount=30;
    }

Example 4: js check if radio button is checked

if(document.getElementById('gender_Male').checked) {
  //Male radio button is checked
}else if(document.getElementById('gender_Female').checked) {
  //Female radio button is checked
}

Example 5: check if one of the radio button is checked

if ($('input[name='+ radioName +']:checked').length) {
           // at least one of the radio buttons was checked
           return true; // allow whatever action would normally happen to continue
      }
      else {
           // no radio button was checked
           return false; // stop whatever action would normally happen
      }