JSFiddle - React, Tailwind, and code Playground
by Ali Uygur
HTML
<div>
<form name="myform" action="">
<label for="name">Name</label>
<input type="text" name="name"></input>
<br>
<label for="select_value" onchange="myFunction()">Select Number</label>
<select name="select_value">
<option value="0">0</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
<br>
<label for="radio_value">Select Position</label>
<input type="radio" name="radio_value" value="First">First</input>
<input type="radio" name="radio_value" value="Second">Second</input>
<input type="radio" name="radio_value" value="Third">Third</input>
<input type="radio" name="radio_value" value="Fourth">Fourth</input>
<input type="radio" name="radio_value" value="Fifth">Fifth</input>
<br>
<input type="submit" name="form_submit" value="Submit"></input>
</form>
</div>
JavaScript
var select = document.getElementsByTagName('select')[0];
select.onchange = function(event) {
var btns = document.querySelectorAll('[name^="radio_value"]');
btns[event.target.value].checked = true
}