<!DOCTYPE html>
<html>
<body>
<p>Click the button to alert the string with removed whitespace.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myTrim(x) {
return x.replace(/^\s+|\s+$/gm,'');
}
function myFunction() {
var str = myTrim(" Hello World! ");
alert(str);
}
</script>
</body>
</html>