накидал рабочий пример
<html>
<head>
</head>
<body><div>123123</div></body>
<script>
function Cl (selector) {
this.obj = document.querySelector(selector);
this.obj.onclick = Cl.prototype.method.bind(this);
}
Cl.prototype.method = function (e) {
console.log(e);
console.log(this);
}
var obj = new Cl('div');
</script>
</html>