js 绑定事件 适用于任何浏览器的元素绑定

function eventBind(obj, eventType, callBack) {
        if (obj.addEventListener) {
            obj.addEventListener(eventType, callBack, false);
        }
        else if (window.attachEvent) {
            obj.attachEvent('on' + eventType, callBack);
        }
        else {
            obj['on' + eventType] = callBack;
        }
    };
eventBind(document, 'click', bodyClick);