run javascript when button click code example
Example: onclick in js
<input type="text" name="text" id="test" onmouseover="skriv('klick')">
<input type="button" name="send" value="Skicka" id="klick" onclick="skriv('test')">
<script src="lib/script.js"></script>
// in lib/script.js
function skriv(name) {
document.getElementById(name).style.backgroundColor='red';
}