JS函數addEventListener的瀏覽器差別性封裝

IE8及更早的版本不支持 addEventListener()函數,所以須要一個標準的函數將這些差別性作封裝:

1 function addListener(target, type, handler) {
2     if (target.addEventListener) {
3         target.addEventListener(type, handler, false);
4     } else if (target.attachEvent) {
5         target.attachEvent("on" + type, handler);
6     } else {
7         target["on" + type] = handler;
8     }
9 }

使用 addListener()函數:

1 function doSomeThing() {
2     // 代碼
3 }
4 var btn = document.getElementById("action-btn");
5 addListener(btn, "click", doSomeTing);