一、John Resig 所写的 addEvent() 函数:http://ejohn.org/projects/flexible-javascript-events/ functionaddEvent( obj, type, fn ) { if( obj.attachEvent ) { obj['e'+type+fn]=fn; obj[type+fn]=function(){obj['e'+type+fn]( window.event );} obj.attachEvent('on'+type, obj[type+fn...
var addClass = function(dom, className) { if (!dom) return; if ('length' in dom) { return dom.forEach(function(elem){ addClass(elem, className); }); } if (dom.classList) return dom.classList.add(className); dom.className += ' ' + className; }; var removeClass = function(dom...
一、addEvent() 作用: 为目标元素绑定事件(如 click) 源码: //addEvent即为DOM元素绑定事件 // a counter used to create unique IDs //为每一个事件添加唯一的id addEvent.guid = 1; function addEvent(element, type, handler) { // assign each event handler a unique ID //如果用户自定义的回调函...
事件(event)是用户在访问页面时执行的操作。提交表单和在图像上移动鼠标就是两种事件。当浏览器探测到一个事件时,比如用鼠标单击或按键,它可以触发与这个事件相关联的JavaScript对象,这些对象称为事件处理程序(eventhandler)或者叫做事件侦听器。。 1.设置HTML标签属性为事件处理程序(避免使用) (1)直接将JS代码写在HTM...
function addEvent(target, name, fn) { if (target.addEventListener) { target.addEventListener(name, fn, false); } else if (target.attachEvent) { target.attachEvent("on" + name, fn); } else { target["on" + name] = fn; } }
WebComm.getOS() == "MSIE"){obj.releaseCapture ();}else{document.removeEventListener("mousemove",WebComm.MoveDiv,false);}a) function addEvent(el, type, fn){if(el.attachEvent){el['e’+type+fn] = fn;el[type+fn] = function(){el[‘e’+type+fn](window.event);}el....
Add an event handler To make the button do something when you select it, you need an event handler in your JavaScript file. An event handler is a way to run a JavaScript function when an event happens on the page. For the button, let's add an event handler for the click event; the...
const em = new EventManager(); em.addEventListner('hello', function() { console.log('hi'); }); em.dispatchEvent('hello'); // hi 这些都比较好理解。下面我们的挑战是: 将以上 20 多行命令式的代码,转换为 7 行 2 个表达式的声明式代码; ...
method enables us to attach an event handler to an element. we can also add multiple event handlers to an element. removeeventlistener() allows us to remove an event listener/handler from a specific element. event object when an event occurs, it belongs to a specific event object. the ...
移除事件处理程序：每当事件处理程序指定给元素时，运行中的浏览器代码与支持页面交互的JS代码之间就会建立一个连接；这种连接越多，页面执行起来就越慢；可以采用事件委托技术，限制连接数量；另外，在不需要的时间移除事件处理程序；内存在留有那些过时不用的“空事件处理程序”（dangling event handler），也是造成Web...