DOM Event(事件)
事件类型
onclick 当用户点击某个对象时调用的事件句柄。 ondblclick 当用户双击某个对象时调用的事件句柄。 onfocus 元素获得焦点。 练习:输入框 onblur 元素失去焦点。 应用场景:用于表单验证,用户离开某个输入框时,代表已经输入完了,我们可以对它进行验证. onchange 域的内容被改变。 应用场景:通常用于表单元素,当元素内容被改变时触发.(三级联动) onkeydown 某个键盘按键被按下。 应用场景: 当用户在最后一个输入框按下回车按键时,表单提交. onkeypress 某个键盘按键被按下并松开。 onkeyup 某个键盘按键被松开。
onload 一张页面或一幅图像完成加载。
onmousedown 鼠标按钮被按下。 onmousemove 鼠标被移动。 onmouseout 鼠标从某元素移开。 onmouseover 鼠标移到某元素之上。 onmouseleave 鼠标从元素离开 onselect 文本被选中。 onsubmit 确认按钮被点击。
绑定事件方式
方式1:
<div id="div" onclick="foo(this)">点我呀</div>
<script>
function foo(self){ // 形参不能是this;
console.log("点你大爷!");
console.log(self);
}
</script>
方式2:
<p id="abc">试一试!</p>
<script>
var ele=document.getElementById("abc");
ele.onclick=function(){
console.log("ok");
console.log(this); // this直接用
};
</script>
事件介绍
1、onload:
onload 属性开发中 只给 body元素加.这个属性的触发 标志着 页面内容被加载完成.应用场景: 当有些事情我们希望页面加载完立刻执行,那么可以使用该事件属性.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script>
/*
window.onload=function(){
var ele=document.getElementById("ppp");
ele.onclick=function(){
alert(123)
};
};
*/
function fun() {
var ele=document.getElementById("ppp");
ele.onclick=function(){
alert(123)
};
}
</script>
</head>
<body onload="fun()">
<p id="ppp">hello p</p>
</body>
</html>
2、onsubmit:
当表单在提交时触发. 该属性也只能给form元素使用.应用场景: 在表单提交前验证用户输入是否正确.如果验证失败.在该方法中我们应该阻止表单的提交.

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script>
window.onload=function(){
//阻止表单提交方式1().
//onsubmit 命名的事件函数,可以接受返回值. 其中返回false表示拦截表单提交.其他为放行.
var ele=document.getElementById("form");
ele.onsubmit=function(event) {
// alert("验证失败 表单不会提交!");
// return false;
// 阻止表单提交方式2 event.preventDefault(); ==>通知浏览器不要执行与事件关联的默认动作。
alert("验证失败 表单不会提交!");
event.preventDefault();
}
};
</script>
</head>
<body>
<form id="form">
<input type="text"/>
<input type="submit" value="点我!" />
</form>
</body>
</html>
3、事件传播:

<div id="abc_1" style="border:1px solid red;300px;height:300px;">
<div id="abc_2" style="border:1px solid red;200px;height:200px;">
</div>
</div>
<script type="text/javascript">
document.getElementById("abc_1").onclick=function(){
alert('111');
};
document.getElementById("abc_2").onclick=function(event){
alert('222');
event.stopPropagation(); //阻止事件向外层div传播.
}
</script>
4、onselect:

<input type="text">
<script>
var ele=document.getElementsByTagName("input")[0];
ele.onselect=function(){
alert(123);
}
</script>
5、onchange:

<select name="" id="">
<option value="">111</option>
<option value="">222</option>
<option value="">333</option>
</select>
<script>
var ele=document.getElementsByTagName("select")[0];
ele.onchange=function(){
alert(123);
}
</script>
6、onkeydown:
Event 对象:Event 对象代表事件的状态,比如事件在其中发生的元素、键盘按键的状态、鼠标的位置、鼠标按钮的状态。
事件通常与函数结合使用,函数不会在事件发生前被执行!event对象在事件发生时系统已经创建好了,并且会在事件函数被调用时传给事件函数.我们获得仅仅需要接收一下即可.比如onkeydown,我们想知道哪个键被按下了,需要问下event对象的属性,这里就时KeyCode.

<input type="text" id="t1"/>
<script type="text/javascript">
var ele=document.getElementById("t1");
ele.onkeydown=function(e){
e=e||window.event;
var keynum=e.keyCode;
var keychar=String.fromCharCode(keynum);
alert(keynum+'----->'+keychar);
};
</script>
7、onmouseout与onmouseleave事件的区别:

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
#container{
300px;
}
#title{
cursor: pointer;
background: #ccc;
}
#list{
display: none;
background:#fff;
}
#list div{
line-height: 50px;
}
#list .item1{
background-color: green;
}
#list .item2{
background-color: rebeccapurple;
}
#list .item3{
background-color: lemonchiffon;
}
</style>
</head>
<body>
<p>先看下使用mouseout的效果:</p>
<div id="container">
<div id="title">使用了mouseout事件↓</div>
<div id="list">
<div class="item1">第一行</div>
<div class="item2">第二行</div>
<div class="item3">第三行</div>
</div>
</div>
<script>
// 1.不论鼠标指针离开被选元素还是任何子元素,都会触发 mouseout 事件。
// 2.只有在鼠标指针离开被选元素时,才会触发 mouseleave 事件。
var container=document.getElementById("container");
var title=document.getElementById("title");
var list=document.getElementById("list");
title.onmouseover=function(){
list.style.display="block";
};
container.onmouseleave=function(){ // 改为mouseout试一下
list.style.display="none";
};
/*
因为mouseout事件是会冒泡的,也就是onmouseout事件可能被同时绑定到了container的子元素title和list
上,所以鼠标移出每个子元素时也都会触发我们的list.style.display="none";
*/
/*
思考:
if:
list.onmouseout=function(){
list.style.display="none";
};
为什么移出第一行时,整个list会被隐藏?
其实是同样的道理,onmouseout事件被同时绑定到list和它的三个子元素item上,所以离开任何一个
子元素同样会触发list.style.display="none";
*/
</script>
</body>
</html>
实例
1、搜索框

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script>
function Focus(){
var input=document.getElementById("ID1");
if (input.value=="请输入用户名"){
input.value="";
}
}
function Blurs(){
var ele=document.getElementById("ID1");
var val=ele.value;
if(!val.trim()){
ele.value="请输入用户名";
}
}
</script>
</head>
<body>
<input id="ID1" type="text" value="请输入用户名" onblur="Blurs()" onfocus="Focus()">
</body>
</html>
2、模态对话框

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
.back{
background-color: white;
height: 2000px;
}
.shade{
position: fixed;
top: 0;
bottom: 0;
left:0;
right: 0;
background-color: grey;
opacity: 0.4;
}
.hide{
display: none;
}
.models{
position: fixed;
top: 50%;
left: 50%;
margin-left: -100px;
margin-top: -100px;
height: 200px;
200px;
background-color: wheat;
}
</style>
</head>
<body>
<div class="back">
<input class="c" type="button" value="click">
</div>
<div class="shade hide handles"></div>
<div class="models hide handles">
<input class="c" type="button" value="cancel">
</div>
<script>
var eles=document.getElementsByClassName("c");
var handles=document.getElementsByClassName("handles");
for(var i=0;i<eles.length;i++){
eles[i].onclick=function(){
if(this.value=="click"){
for(var j=0;j<handles.length;j++){
handles[j].classList.remove("hide");
}
}
else {
for(var j=0;j<handles.length;j++){
handles[j].classList.add("hide");
}
}
}
}
</script>
</body>
</html>
3、表格案例

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<button class="select_all">全选</button>
<button class="select_reverse">反选</button>
<button class="cancel">取消</button>
<hr>
<table class="server_table" border="2px" cellspacing="2px">
<tr>
<td><input type="checkbox" class="item"></td>
<td>111</td>
<td>111</td>
<td>111</td>
</tr>
<tr>
<td><input type="checkbox" class="item"></td>
<td>222</td>
<td>222</td>
<td>222</td>
</tr>
<tr>
<td><input type="checkbox" class="item"></td>
<td>333</td>
<td>333</td>
<td>333</td>
</tr>
<tr>
<td><input type="checkbox" class="item"></td>
<td>444</td>
<td>444</td>
<td>444</td>
</tr>
</table>
<script>
/*
var ele_all=document.getElementsByClassName("select_all")[0];
var ele_reverse=document.getElementsByClassName("select_reverse")[0];
var ele_cancel=document.getElementsByClassName("cancel")[0];
var input_arr=document.getElementsByClassName("item");
ele_all.onclick=function(){
for(var i=0;i<input_arr.length;i++){
console.log(input_arr[i]);
var input=input_arr[i];
input.checked=true;
}
};
ele_cancel.onclick=function(){
for(var i=0;i<input_arr.length;i++){
console.log(input_arr[i]);
var input=input_arr[i];
input.checked=false;
}
};
ele_reverse.onclick=function(){
for(var i=0;i<input_arr.length;i++){
console.log(input_arr[i]);
var input=input_arr[i];
if(input.checked){
input.checked=false;
}
else{
input.checked=true;
}
}
};
*/
var input_arr=document.getElementsByClassName("item");
var button_arr=document.getElementsByTagName("button");
for(var i=0;i<button_arr.length;i++){
button_arr[i].onclick=function(){
for (var j=0;j<input_arr.length;j++){
var inp=input_arr[j]
if(this.innerText=="全选"){
console.log("ok");
inp.checked=true;
}
else if(this.innerText=="取消"){
inp.checked=false;
}
else {
if(inp.checked){
inp.checked=false;
}else {
inp.checked=true;
}
}
}
}
}
</script>
</body>
</html>
4、select移动

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
.outer{
margin: 0 auto;
background-color: darkgray;
80%;
height: 600px;margin-top: 30px;
word-spacing: -5px;
}
#left{
display: inline-block;
100px ;
height: 140px;
background-color: wheat;
text-align: center;
}
#choice{
display: inline-block;
height: 140px;
background-color: darkolivegreen;
vertical-align: top;
padding:0 5px;
}
#choice button{
margin-top: 20px;
}
#right{
display: inline-block;
100px ;
height: 140px;
background-color: wheat;
text-align: center;
line-height: 140px;
}
</style>
</head>
<body>
<div class="outer">
<select multiple="multiple" size="5" id="left">
<option>红楼梦</option>
<option>西游记</option>
<option>水浒传</option>
<option>JinPingMei</option>
<option>三国演义</option>
</select>
<span id="choice">
<button id="choose_move"> > </button><br>
<button id="all_move"> >> </button>
</span>
<select multiple="multiple" size="10" id="right">
<option>放风筝的人</option>
</select>
</div>
<script>
var choose_move=document.getElementById("choose_move");
var all_move=document.getElementById("all_move");
var right=document.getElementById("right");
var left=document.getElementById("left");
var options=left.options;
choose_move.onclick=function(){
for (var i=0; i<options.length;i++){
var option=options[i];
if(option.selected==true){
// var news=option.cloneNode(true);
// console.log(news);
right.appendChild(option);
i--;
}
}
};
all_move.onclick=function(){
for (var i=0; i<options.length;i++){
var option=options[i];
right.appendChild(option);
i--;
};
};
/*
var buttons=document.getElementsByTagName("button");
for(var i=0;i<buttons.length;i++) {
buttons[i].onclick = function () {
for (var i = 0; i < options.length; i++) {
var option = options[i];
if (this.innerText == ">") {
if (option.selected == true) {
// var news=option.cloneNode(true);
// console.log(news);
right.appendChild(option);
i--;
}
} else {
right.appendChild(option);
i--;
}
}
};
}
*/
</script>
</body>
</html>
5、二级联动

<select id="province">
<option>请选择省:</option>
</select>
<select id="city">
<option>请选择市:</option>
</select>
<script>
data={"河北省":["廊坊","邯郸"],"北京":["朝阳区","海淀区"]};
var p=document.getElementById("province");
var c=document.getElementById("city");
for(var i in data){
var option_pro=document.createElement("option");
option_pro.innerHTML=i;
p.appendChild(option_pro);
}
p.onchange=function(){
pro=(this.options[this.selectedIndex]).innerHTML;
citys=data[pro];
c.options.length=0;
for (var i in citys){
var option_city=document.createElement("option");
option_city.innerHTML=citys[i];
c.appendChild(option_city);
}
}
</script>
6、跑马灯与tab切换

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>tab</title>
<style>
*{margin:0; padding:0; list-style:none;}
body{
font-family: "Helvetica Neue", "Hiragino Sans GB", "Microsoft YaHei", "9ED14F53", Arial, sans-serif;
}
h3{
text-align: center;
color:darkcyan;
margin-top: 30px;
letter-spacing: 5px;
}
.box{
1000px;
margin:50px auto 0px;
}
#title{
line-height: 40px;
background-color: rgb(247,247,247);
font-size: 16px;
font-weight: bold;
color: rgb(102,102,102);
}
#title span{
float: left;
166px;
text-align: center;
}
#title span:hover{
/*color: black;*/
cursor: pointer;
}
#content{
margin-top: 20px;
}
#content li{
1050px;
display: none;
background-color: rgb(247,247,247);
}
#content li div{
156px;
margin-right: 14px;
float: left;
text-align: center;
}
#content li div a{
font-size: 14px;
color: black;
line-height: 14px;
/* float: left;*/
display: inline-block;
margin-top: 10px;
}
#content li a:hover{
color: #B70606;
}
#content li div span{
font-size: 16px;
line-height: 16px;
/*float: left;*/
display: block;
color: rgb(102,102,102);
margin-top: 10px;
}
#content img{
float: left;
155px;
height: 250px;
}
#title .select{
background-color: #2459a2;
color: white;
border-radius: 10%;
}
#content .show{
display: block;
}
.show span{
color: red!important;
font-size: 30px;
}
</style>
</head>
<body>
<h3 id="wel">京东商城欢迎您</h3>
<!-- direction="right up down left" -->
<!-- behavior:滚动方式(包括3个值:scroll、slide、alternate) -->
<!-- 说明:scroll:循环滚动,默认效果;slide:只滚动一次就停止;alternate:来回交替进行滚动。 -->
<!-- scrollamount="5" 滚动速度 -->
<marquee behavior="scroll" direction="right">欢迎您苑昊先生</marquee>
<script>
function test(){
var mywel = document.getElementById("wel");
var content = mywel.innerText;
var f_content = content.charAt(0);
var l_content = content.substring(1,content.length);
var new_content = l_content + f_content;
mywel.innerText = new_content;
}
// setInterval("test();", 500);
</script>
<div class="box">
<p id="title">
<span class="select">家用电器</span>
<span>家具</span>
<span>汽车</span>
<span>食品</span>
<span>女鞋</span>
<span>医疗保健</span>
</p>
<ul id="content">
<li class="show">
<div><img src="https://img10.360buyimg.com/n1/s450x450_jfs/t4786/325/2470647304/119102/9e1a4ed5/59005841Nd786a8df.jpg" alt="冰箱"><a href="#">容声(Ronshen)冰箱</a><span>价格:5600</span></div>
<div><img src="https://img12.360buyimg.com/n1/s450x450_jfs/t3037/347/1290968859/201366/7c1028a0/57c00194N9d0a54c6.jpg" alt="洗衣机"><a href="#">海尔洗衣机</a><span>价格:5400</span></div>
<div><img src="https://img11.360buyimg.com/n1/jfs/t3289/128/2393835119/236360/af1d283b/57e0f300N53dde603.jpg" alt="电饭煲"><a href="#">福库(CUCKOO)电饭煲</a><span>价格:3999</span></div>
<div><img src="https://img13.360buyimg.com/n1/jfs/t3235/137/2361713777/152258/a6908440/57e098c2N44a90a5d.jpg" alt="智能电视"><a href="#">三星智能电视</a><span>价格:8999</span></div>
<div><img src="https://img10.360buyimg.com/n1/jfs/t2053/101/1391591157/215066/572e131b/5696ee9bN2376492d.jpg" alt="净水器"><a href="#">净水器</a><span>价格:1300</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t3175/78/2357430273/262835/9a8e7f65/57e0a3e9Nbda39dd2.jpg" alt="空气净化器"><a href="#">空气净化器</a><span>价格:5300</span></div>
</li>
<li>
<div><img src="https://img12.360buyimg.com/n1/jfs/t1948/172/2877517581/556924/682eb107/56f63dc8Naddf77e5.jpg" alt="沙发"><a href="#">沙发</a><span>价格:2900</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t1948/172/2877517581/556924/682eb107/56f63dc8Naddf77e5.jpg" alt="沙发"><a href="#">沙发</a><span>价格:2900</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t1948/172/2877517581/556924/682eb107/56f63dc8Naddf77e5.jpg" alt="沙发"><a href="#">沙发</a><span>价格:2900</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t1948/172/2877517581/556924/682eb107/56f63dc8Naddf77e5.jpg" alt="沙发"><a href="#">沙发</a><span>价格:2900</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t1948/172/2877517581/556924/682eb107/56f63dc8Naddf77e5.jpg" alt="沙发"><a href="#">沙发</a><span>价格:2900</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t1948/172/2877517581/556924/682eb107/56f63dc8Naddf77e5.jpg" alt="沙发"><a href="#">沙发</a><span>价格:2900</span></div>
</li>
<li>
<div><img src="http://img11.360buyimg.com/n1/jfs/t4969/76/45396935/144539/347153d4/58d9cff4N36872ad6.jpg" alt="长安汽车"><a href="#">长安汽车</a><span>价格:12900</span></div>
<div><img src="http://img11.360buyimg.com/n1/jfs/t4969/76/45396935/144539/347153d4/58d9cff4N36872ad6.jpg" alt="长安汽车"><a href="#">长安汽车</a><span>价格:12900</span></div>
<div><img src="http://img11.360buyimg.com/n1/jfs/t4969/76/45396935/144539/347153d4/58d9cff4N36872ad6.jpg" alt="长安汽车"><a href="#">长安汽车</a><span>价格:12900</span></div>
<div><img src="http://img11.360buyimg.com/n1/jfs/t4969/76/45396935/144539/347153d4/58d9cff4N36872ad6.jpg" alt="长安汽车"><a href="#">长安汽车</a><span>价格:12900</span></div>
<div><img src="http://img11.360buyimg.com/n1/jfs/t4969/76/45396935/144539/347153d4/58d9cff4N36872ad6.jpg" alt="长安汽车"><a href="#">长安汽车</a><span>价格:12900</span></div>
<div><img src="http://img11.360buyimg.com/n1/jfs/t4969/76/45396935/144539/347153d4/58d9cff4N36872ad6.jpg" alt="长安汽车"><a href="#">长安汽车</a><span>价格:12900</span></div>
</li>
<li>
<div><img src="https://img14.360buyimg.com/n1/jfs/t4414/110/2582917360/207971/b7e129ad/58f0ee1fN94425de1.jpg" alt="嘉兴粽子"><a href="#">嘉兴粽子</a><span>价格:1</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t4414/110/2582917360/207971/b7e129ad/58f0ee1fN94425de1.jpg" alt="嘉兴粽子"><a href="#">嘉兴粽子</a><span>价格:1</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t4414/110/2582917360/207971/b7e129ad/58f0ee1fN94425de1.jpg" alt="嘉兴粽子"><a href="#">嘉兴粽子</a><span>价格:1</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t4414/110/2582917360/207971/b7e129ad/58f0ee1fN94425de1.jpg" alt="嘉兴粽子"><a href="#">嘉兴粽子</a><span>价格:1</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t4414/110/2582917360/207971/b7e129ad/58f0ee1fN94425de1.jpg" alt="嘉兴粽子"><a href="#">嘉兴粽子</a><span>价格:1</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t4414/110/2582917360/207971/b7e129ad/58f0ee1fN94425de1.jpg" alt="嘉兴粽子"><a href="#">嘉兴粽子</a><span>价格:1</span></div>
</li>
<li>
<div><img src="https://img14.360buyimg.com/n1/jfs/t3079/298/5759209435/92674/14818594/587f1c33N53e5d2a9.jpg" alt="星期六"><a href="#">星期六</a><span>价格:439</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t3079/298/5759209435/92674/14818594/587f1c33N53e5d2a9.jpg" alt="星期六"><a href="#">星期六</a><span>价格:439</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t3079/298/5759209435/92674/14818594/587f1c33N53e5d2a9.jpg" alt="星期六"><a href="#">星期六</a><span>价格:439</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t3079/298/5759209435/92674/14818594/587f1c33N53e5d2a9.jpg" alt="星期六"><a href="#">星期六</a><span>价格:439</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t3079/298/5759209435/92674/14818594/587f1c33N53e5d2a9.jpg" alt="星期六"><a href="#">星期六</a><span>价格:439</span></div>
<div><img src="https://img14.360buyimg.com/n1/jfs/t3079/298/5759209435/92674/14818594/587f1c33N53e5d2a9.jpg" alt="星期六"><a href="#">星期六</a><span>价格:439</span></div>
</li>
<li>
<div><img src="https://img12.360buyimg.com/n1/jfs/t5755/127/1139389729/356866/99d4e869/5923e410Nb2983f70.jpg" alt="汇仁 肾宝片"><a href="#">汇仁 肾宝片</a><span>价格:322</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t5755/127/1139389729/356866/99d4e869/5923e410Nb2983f70.jpg" alt="汇仁 肾宝片"><a href="#">汇仁 肾宝片</a><span>价格:322</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t5755/127/1139389729/356866/99d4e869/5923e410Nb2983f70.jpg" alt="汇仁 肾宝片"><a href="#">汇仁 肾宝片</a><span>价格:322</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t5755/127/1139389729/356866/99d4e869/5923e410Nb2983f70.jpg" alt="汇仁 肾宝片"><a href="#">汇仁 肾宝片</a><span>价格:322</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t5755/127/1139389729/356866/99d4e869/5923e410Nb2983f70.jpg" alt="汇仁 肾宝片"><a href="#">汇仁 肾宝片</a><span>价格:322</span></div>
<div><img src="https://img12.360buyimg.com/n1/jfs/t5755/127/1139389729/356866/99d4e869/5923e410Nb2983f70.jpg" alt="汇仁 肾宝片"><a href="#">汇仁 肾宝片</a><span>价格:322</span></div>
</li>
</ul>
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