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Python javascript操作DOM

2017-04-06 23:45 337 查看
文档对象模型(Document Object Model,DOM)是一种用于HTML和XML文档的编程接口。它给文档提供了一种结构化的表示方法,可以改变文档的内容和呈现方式。我们最为关心的是,DOM把网页和脚本以及其他的编程语言联系了起来。DOM属于浏览器,而不是JavaScript语言规范里的规定的核心内容。这里我们主要是讲用javascript操作DOM。

1. 查找元素

1.1 直接查找

document.getElementById             根据ID获取一个标签
document.getElementsByName          根据name属性获取标签集合
document.getElementsByClassName     根据class属性获取标签集合
document.getElementsByTagName       根据标签名获取标签集合


1.2 间接查找

parentNode          // 父节点
childNodes          // 所有子节点
firstChild          // 第一个子节点
lastChild           // 最后一个子节点
nextSibling         // 下一个兄弟节点
previousSibling     // 上一个兄弟节点
parentElement           // 父节点标签元素
children                // 所有子标签
firstElementChild       // 第一个子标签元素
lastElementChild        // 最后一个子标签元素
nextElementtSibling     // 下一个兄弟标签元素
previousElementSibling  // 上一个兄弟标签元素


2. 操作

2.1 内容

innerText   文本
outerText
innerHTML   HTML内容
innerHTML
value       值
input    value获取当前标签中的值
select   获取选中的value值(selectedIndex)
textarea value获取当前标签中的值


<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf8">
<title>JS3</title>

</head>
<body>

<!--  先生成一个html文件,文件内容如下:-->
<div id="div1">
<p id="p1">我是第一个标签</p>
<p id="p2">我是第<b>二</b>个标签</p>
<input id="i1" type="text" value="我是i1"/>
<select id="i2" name="city" size="2" multiple="multiple">
<option value="1">北京</option>
<option value="2">上海</option>
<option value="3">南京</option>
<option value="4" selected="selected">邯郸</option>
</select>
<textarea name="linearea" id="i3">默认数据</textarea>
</div>
<script type="text/javascript">
//操作内容
document.getElementById("p1").innerText;
document.getElementById("p1").textContent;
document.getElementById("p1").textContent="我是p1,我被改了!"
document.getElementById("p2").textContent;
document.getElementById("p2").innerHTML;
document.getElementById("i1").value;
document.getElementById("i2").value;
document.getElementById("i3").value;
</script>

</body>

</html>


  

2.2 属性

attributes                // 获取所有标签属性
setAttribute(key,value)   // 设置标签属性
getAttribute(key)         // 获取指定标签属性

/*
var atr = document.createAttribute("class");
atr.nodeValue="democlass";
document.getElementById('n1').setAttributeNode(atr);
*/


示例:

<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf8">
<title>示例</title>
</head>
<body>
<input type="button" value="全选"  onclick="CheckAll();"/>
<input type="button" value="取消" onclick="CancelAll();"/>
<input type="button" value="反选" onclick="ReverseCheck();"/>

<table border="1" >
<thead>

</thead>
<tbody id="tb">
<tr>
<td><input type="checkbox" /></td>
<td>111</td>
<td>222</td>
</tr>
<tr>
<td><input type="checkbox" /></td>
<td>111</td>
<td>222</td>
</tr>
<tr>
<td><input type="checkbox" /></td>
<td>111</td>
<td>222</td>
</tr>
<tr>
<td><input type="checkbox" /></td>
<td>111</td>
<td>222</td>
</tr>
</tbody>
</table>
<script>
function CheckAll(ths){
var tb = document.getElementById('tb');
var trs = tb.childNodes;
for(var i =0; i<trs.length; i++){

var current_tr = trs[i];
if(current_tr.nodeType==1){
var inp = current_tr.firstElementChild.getElementsByTagName('input')[0];
inp.checked = true;
}
}
}

function CancelAll(ths){
var tb = document.getElementById('tb');
var trs = tb.childNodes;
for(var i =0; i<trs.length; i++){

var current_tr = trs[i];
if(current_tr.nodeType==1){
var inp = current_tr.firstElementChild.getElementsByTagName('input')[0];
inp.checked = false;
}
}
}

function ReverseCheck(ths){
var tb = document.getElementById('tb');
var trs = tb.childNodes;
for(var i =0; i<trs.length; i++){
var current_tr = trs[i];
if(current_tr.nodeType==1){
var inp = current_tr.firstElementChild.getElementsByTagName('input')[0];
if(inp.checked){
inp.checked = false;
}else{
inp.checked = true;
}
}
}
}

</script>
</body>
</html>


2.3 class操作

className                // 获取所有类名
classList.remove(cls)    // 删除指定类
classList.add(cls)       // 添加类


2.4 标签操作

a.创建标签

// 方式一
var tag = document.createElement('a')
tag.innerText = "qianyuliang"
tag.className = "q1"
tag.href = "http://www.cnblogs.com/qianyuliang"

// 方式二
var tag = "<a class='q1' href='http://www.cnblogs.com/qianyuliang'>qianyuliang</a>"


b.操作标签

// 方式一
var obj = "<input type='text' />";
xxx.insertAdjacentHTML("beforeEnd",obj);
xxx.insertAdjacentElement('afterBegin',document.createElement('p'))

//注意:第一个参数只能是'beforeBegin'、 'afterBegin'、 'beforeEnd'、 'afterEnd'

// 方式二
var tag = document.createElement('a')
xxx.appendChild(tag)
xxx.insertBefore(tag,xxx[1])


2.5 样式操作

var obj = document.getElementById('i1')

obj.style.fontSize = "32px";
obj.style.backgroundColor = "red";


<input onfocus="Focus(this);" onblur="Blur(this);" id="search" value="请输入关键字" style="color: gray;" />

<script>
function Focus(ths){
ths.style.color = "black";
if(ths.value == '请输入关键字' || ths.value.trim() == ""){

ths.value = "";
}
}

function Blur(ths){
if(ths.value.trim() == ""){
ths.value = '请输入关键字';
ths.style.color = 'gray';
}else{
ths.style.color = "black";
}
}
</script>


2.6 位置操作

总文档高度
document.documentElement.offsetHeight

当前文档占屏幕高度
document.documentElement.clientHeight

自身高度
tag.offsetHeight

距离上级定位高度
tag.offsetTop

父定位标签
tag.offsetParent

滚动高度
tag.scrollTop

/*
clientHeight -> 可见区域:height + padding
clientTop    -> border高度
offsetHeight -> 可见区域:height + padding + border
offsetTop    -> 上级定位标签的高度
scrollHeight -> 全文高:height + padding
scrollTop    -> 滚动高度
特别的:
document.documentElement代指文档根节点
*/


<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf8">
<title>示例</title>
</head>
<body style="margin:0;">
<div style="height:900px;">

</div>
<div style="padding: 10px;">
<div id="i1" style="height:190px;padding:2px;border:1px solid red;margin:8px;">
<p>asdf</p>
<p>asdf</p>
<p>asdf</p>
<p>asdf</p>
<p>asdf</p>
</div>
</div>

<script>
var i1 = document.getElementById('i1');

console.log(i1.clientHeight); // 可见区域:height + padding
console.log(i1.clientTop);    // border高度
console.log('=====');
console.log(i1.offsetHeight); // 可见区域:height + padding + border
console.log(i1.offsetTop);    // 上级定位标签的高度
console.log('=====');
console.log(i1.scrollHeight);   //全文高:height + padding
console.log(i1.scrollTop);      // 滚动高度
console.log('=====');

</script>
</body>
</html>




  

<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<style>

body{
margin: 0px;
}
img {
border: 0;
}
ul{
padding: 0;
margin: 0;
list-style: none;
}
.clearfix:after {
content: ".";
display: block;
height: 0;
clear: both;
visibility: hidden;
}

.wrap{
width: 980px;
margin: 0 auto;
}

.pg-header{
background-color: #303a40;
-webkit-box-shadow: 0 2px 5px rgba(0,0,0,.2);
-moz-box-shadow: 0 2px 5px rgba(0,0,0,.2);
box-shadow: 0 2px 5px rgba(0,0,0,.2);
}
.pg-header .logo{
float: left;
padding:5px 10px 5px 0px;
}
.pg-header .logo img{
vertical-align: middle;
width: 110px;
height: 40px;

}
.pg-header .nav{
line-height: 50px;
}
.pg-header .nav ul li{
float: left;
}
.pg-header .nav ul li a{
display: block;
color: #ccc;
padding: 0 20px;
text-decoration: none;
font-size: 14px;
}
.pg-header .nav ul li a:hover{
color: #fff;
background-color: #425a66;
}
.pg-body{

}
.pg-body .catalog{
position: absolute;
top:60px;
width: 200px;
background-color: #fafafa;
bottom: 0px;
}
.pg-body .catalog.fixed{
position: fixed;
top:10px;
}

.pg-body .catalog .catalog-item.active{
color: #fff;
background-color: #425a66;
}

.pg-body .content{
position: absolute;
top:60px;
width: 700px;
margin-left: 210px;
background-color: #fafafa;
overflow: auto;
}
.pg-body .content .section{
height: 500px;
}
</style>
<body onscroll="ScrollEvent();">
<div class="pg-header">
<div class="wrap clearfix">
<div class="logo">
<a href="#">
<img src="http://core.pc.lietou-static.com/revs/images/common/logo_7012c4a4.pn">
</a>
</div>
<div class="nav">
<ul>
<li>
<a  href="#">首页</a>
</li>
<li>
<a  href="#">功能一</a>
</li>
<li>
<a  href="#">功能二</a>
</li>
</ul>
</div>

</div>
</div>
<div class="pg-body">
<div class="wrap">
<div class="catalog">
<div class="catalog-item" auto-to="function1"><a>第1张</a></div>
<div class="catalog-item" auto-to="function2"><a>第2张</a></div>
<div class="catalog-item" auto-to="function3"><a>第3张</a></div>
</div>
<div class="content">
<div menu="function1" class="section">
<h1>第一章</h1>
</div>
<div menu="function2" class="section">
<h1>第二章</h1>
</div>
<div menu="function3" class="section">
<h1>第三章</h1>
</div>
</div>
</div>

</div>
<script>
function ScrollEvent(){
var bodyScrollTop = document.body.scrollTop;
if(bodyScrollTop>50){
document.getElementsByClassName('catalog')[0].classList.add('fixed');
}else{
document.getElementsByClassName('catalog')[0].classList.remove('fixed');
}

}
</script>
</body>
</html>


<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<style>

body{
margin: 0px;
}
img {
border: 0;
}
ul{
padding: 0;
margin: 0;
list-style: none;
}
h1{
padding: 0;
margin: 0;
}
.clearfix:after {
content: ".";
display: block;
height: 0;
clear: both;
visibility: hidden;
}

.wrap{
width: 980px;
margin: 0 auto;
}

.pg-header{
background-color: #303a40;
-webkit-box-shadow: 0 2px 5px rgba(0,0,0,.2);
-moz-box-shadow: 0 2px 5px rgba(0,0,0,.2);
box-shadow: 0 2px 5px rgba(0,0,0,.2);
}
.pg-header .logo{
float: left;
padding:5px 10px 5px 0px;
}
.pg-header .logo img{
vertical-align: middle;
width: 110px;
height: 40px;

}
.pg-header .nav{
line-height: 50px;
}
.pg-header .nav ul li{
float: left;
}
.pg-header .nav ul li a{
display: block;
color: #ccc;
padding: 0 20px;
text-decoration: none;
font-size: 14px;
}
.pg-header .nav ul li a:hover{
color: #fff;
background-color: #425a66;
}
.pg-body{

}
.pg-body .catalog{
position: absolute;
top:60px;
width: 200px;
background-color: #fafafa;
bottom: 0px;
}
.pg-body .catalog.fixed{
position: fixed;
top:10px;
}

.pg-body .catalog .catalog-item.active{
color: #fff;
background-color: #425a66;
}

.pg-body .content{
position: absolute;
top:60px;
width: 700px;
margin-left: 210px;
background-color: #fafafa;
overflow: auto;
}
.pg-body .content .section{
height: 500px;
border: 1px solid red;
}
</style>
<body onscroll="ScrollEvent();">
<div class="pg-header">
<div class="wrap clearfix">
<div class="logo">
<a href="#">
<img src="http://core.pc.lietou-static.com/revs/images/common/logo_7012c4a4.pn">
</a>
</div>
<div class="nav">
<ul>
<li>
<a  href="#">首页</a>
</li>
<li>
<a  href="#">功能一</a>
</li>
<li>
<a  href="#">功能二</a>
</li>
</ul>
</div>

</div>
</div>
<div class="pg-body">
<div class="wrap">
<div class="catalog" id="catalog">
<div class="catalog-item" auto-to="function1"><a>第1张</a></div>
<div class="catalog-item" auto-to="function2"><a>第2张</a></div>
<div class="catalog-item" auto-to="function3"><a>第3张</a></div>
</div>
<div class="content" id="content">
<div menu="function1" class="section">
<h1>第一章</h1>
</div>
<div menu="function2" class="section">
<h1>第二章</h1>
</div>
<div menu="function3" class="section">
<h1>第三章</h1>
</div>
</div>
</div>

</div>
<script>
function ScrollEvent(){
var bodyScrollTop = document.body.scrollTop;
if(bodyScrollTop>50){
document.getElementsByClassName('catalog')[0].classList.add('fixed');
}else{
document.getElementsByClassName('catalog')[0].classList.remove('fixed');
}

var content = document.getElementById('content');
var sections = content.children;
for(var i=0;i<sections.length;i++){
var current_section = sections[i];

// 当前标签距离顶部绝对高度
var scOffTop = current_section.offsetTop + 60;

// 当前标签距离顶部,相对高度
var offTop = scOffTop - bodyScrollTop;

// 当前标签高度
var height = current_section.scrollHeight;

if(offTop<0 && -offTop < height){
// 当前标签添加active
// 其他移除 active
var menus = document.getElementById('catalog').children;
var current_menu = menus[i];
current_menu.classList.add('active');
for(var j=0;j<menus.length;j++){
if(menus[j] == current_menu){

}else{
menus[j].classList.remove('active');
}
}
break;
}

}

}
</script>
</body>
</html>


 

<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title></title>
</head>
<style>

body{
margin: 0px;
}
img {
border: 0;
}
ul{
padding: 0;
margin: 0;
list-style: none;
}
h1{
padding: 0;
margin: 0;
}
.clearfix:after {
content: ".";
display: block;
height: 0;
clear: both;
visibility: hidden;
}

.wrap{
width: 980px;
margin: 0 auto;
}

.pg-header{
background-color: #303a40;
-webkit-box-shadow: 0 2px 5px rgba(0,0,0,.2);
-moz-box-shadow: 0 2px 5px rgba(0,0,0,.2);
box-shadow: 0 2px 5px rgba(0,0,0,.2);
}
.pg-header .logo{
float: left;
padding:5px 10px 5px 0px;
}
.pg-header .logo img{
vertical-align: middle;
width: 110px;
height: 40px;

}
.pg-header .nav{
line-height: 50px;
}
.pg-header .nav ul li{
float: left;
}
.pg-header .nav ul li a{
display: block;
color: #ccc;
padding: 0 20px;
text-decoration: none;
font-size: 14px;
}
.pg-header .nav ul li a:hover{
color: #fff;
background-color: #425a66;
}
.pg-body{

}
.pg-body .catalog{
position: absolute;
top:60px;
width: 200px;
background-color: #fafafa;
bottom: 0px;
}
.pg-body .catalog.fixed{
position: fixed;
top:10px;
}

.pg-body .catalog .catalog-item.active{
color: #fff;
background-color: #425a66;
}

.pg-body .content{
position: absolute;
top:60px;
width: 700px;
margin-left: 210px;
background-color: #fafafa;
overflow: auto;
}
.pg-body .content .section{
height: 500px;
border: 1px solid red;
}
</style>
<body onscroll="ScrollEvent();">
<div class="pg-header">
<div class="wrap clearfix">
<div class="logo">
<a href="#">
<img src="http://core.pc.lietou-static.com/revs/images/common/logo_7012c4a4.pn">
</a>
</div>
<div class="nav">
<ul>
<li>
<a  href="#">首页</a>
</li>
<li>
<a  href="#">功能一</a>
</li>
<li>
<a  href="#">功能二</a>
</li>
</ul>
</div>

</div>
</div>
<div class="pg-body">
<div class="wrap">
<div class="catalog" id="catalog">
<div class="catalog-item" auto-to="function1"><a>第1张</a></div>
<div class="catalog-item" auto-to="function2"><a>第2张</a></div>
<div class="catalog-item" auto-to="function3"><a>第3张</a></div>
</div>
<div class="content" id="content">
<div menu="function1" class="section">
<h1>第一章</h1>
</div>
<div menu="function2" class="section">
<h1>第二章</h1>
</div>
<div menu="function3" class="section" style="height: 200px;">
<h1>第三章</h1>
</div>
</div>
</div>

</div>
<script>
function ScrollEvent(){
var bodyScrollTop = document.body.scrollTop;
if(bodyScrollTop>50){
document.getElementsByClassName('catalog')[0].classList.add('fixed');
}else{
document.getElementsByClassName('catalog')[0].classList.remove('fixed');
}

var content = document.getElementById('content');
var sections = content.children;
for(var i=0;i<sections.length;i++){
var current_section = sections[i];

// 当前标签距离顶部绝对高度
var scOffTop = current_section.offsetTop + 60;

// 当前标签距离顶部,相对高度
var offTop = scOffTop - bodyScrollTop;

// 当前标签高度
var height = current_section.scrollHeight;

if(offTop<0 && -offTop < height){
// 当前标签添加active
// 其他移除 active

// 如果已经到底部,现实第三个菜单
// 文档高度 = 滚动高度 + 视口高度

var a = document.getElementsByClassName('content')[0].offsetHeight + 60;
var b = bodyScrollTop + document.documentElement.clientHeight;
console.log(a+60,b);
if(a == b){
var menus = document.getElementById('catalog').children;
var current_menu = document.getElementById('catalog').lastElementChild;
current_menu.classList.add('active');
for(var j=0;j<menus.length;j++){
if(menus[j] == current_menu){

}else{
menus[j].classList.remove('active');
}
}
}else{
var menus = document.getElementById('catalog').children;
var current_menu = menus[i];
current_menu.classList.add('active');
for(var j=0;j<menus.length;j++){
if(menus[j] == current_menu){

}else{
menus[j].classList.remove('active');
}
}
}

break;
}

}

}
</script>
</body>
</html>


2.7 提交表单

document.geElementById('form').submit()

2.8 其他操作

console.log                 输出框
alert                       弹出框
confirm                     确认框

// URL和刷新
location.href               获取URL
location.href = "url"       重定向
location.reload()           重新加载

// 定时器
setInterval                 多次定时器
clearInterval               清除多次定时器
setTimeout                  单次定时器
clearTimeout                清除单次定时器


3 事件



对于事件需要注意的要点:

this

event

事件链以及跳出

this标签当前正在操作的标签,event封装了当前事件的内容。

实例:

<!DOCTYPE html>
<html>
<head>
<meta charset='utf-8' />
<title></title>

<style>
.gray{
color:gray;
}
.black{
color:black;
}
</style>
<script type="text/javascript">
function Enter(){
var id= document.getElementById("tip")
id.className = 'black';
if(id.value=='请输入关键字'||id.value.trim()==''){
id.value = ''
}
}
function Leave(){
var id= document.getElementById("tip")
var val = id.value;
if(val.length==0||id.value.trim()==''){
id.value = '请输入关键字'
id.className = 'gray';
}else{
id.className = 'black';
}
}
</script>
</head>
<body>
<input type='text' class='gray' id='tip' value='请输入关键字' onfocus='Enter();'  onblur='Leave();'/>
</body>
</html>


<!DOCTYPE html>
<html>
<head>
<meta charset='utf-8' >
<title>欢迎blue shit莅临指导  </title>
<script type='text/javascript'>
function Go(){
var content = document.title;
var firstChar = content.charAt(0)
var sub = content.substring(1,content.length)
document.title = sub + firstChar;
}
setInterval('Go()',1000);
</script>
</head>
<body>
</body>
</html>


  

 
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