Handle event binding compatibility issues

var btn = document.getElementById ("btn");

if (btn.addEventListener) {// Compatible with IE9 and above, Chrome, Safari, Opera, Firefox
　　btn.addEventListener ("click", dome);
} else if (btn.attachEvent ) {// Compatible with IE8
　　btn.attachEvent ("onlick", dome);
} else {// Compatible with
　　btn.onclick = dome ();
};

function dome; () {
　　// Event body

　　alert ("Event binding succeeded!");
}