JSFiddle - React, Tailwind, and code Playground

by Chan Wu

HTML

<select name="option" id="option">
    <option value="選項1">選項1</option>
    <option value="選項2">選項2</option>
    <option value="選項3">選項3</option>
</select>
<textarea name="content" id="content" cols="30" rows="10"></textarea>

JavaScript

console.clear();

var o = document.getElementById('option');
var c = document.getElementById('content');

o.addEventListener('change', function() {
	c.value = o.value;
});