Registering event handlers within the JavaScript code allows you to use the "this" statement. No need to pass a value to JavaScript functions, instead use "this" to manipulate properties.
Let’s see an example
Live Demo
<!DOCTYPE html>
<html>
<head>
<script>
function display( ) {
click.onclick = styleMe;
uname.onclick = styleMe;
}
function styleMe ( ) {
this.style.backgroundColor = "#000000";
this.style.color = "#FFFFFF";
}
</script>
</head>
<body onload="display()" >
<div id="uname"> Hello Wordl!</div>
<button id="click"> Click</button>
</body>
</html>