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Python全栈开发,Day17 - DOM

本章内容

  1. 查找元素
  2. 操作
  3. 事件

 

前言

 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。

 

一、查找元素

 1、直接查找

document.getElementById              根据ID获取一个标签

document.getElementsByName          根据nam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

 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

nextSibing      //下一个兄弟节点

previousSibing    //上一个兄弟节点

 

parentElment            //父节点标签元素

children          //所有子标签

firstElementChild       //第一个标签元素 

lastElementChild       //最后一个子标签元素

nextElementSibling      //下一个兄弟标签元素

previousElementSibling  //上一个兄弟标签元素

 

二、操作

 1、内容

innerText    文本

outerText

innerHTML   HTML内容

innerHTML

value      值

 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 = "http://www.mamicode.com/democlass";

  document.getElementById(‘n1‘).setAttributeNode(atr);

  */

技术分享
 1 <!DOCTYPE html>
 2 <html>
 3 <head lang="en">
 4     <meta charset="UTF-8">
 5     <title></title>
 6 </head>
 7 <body>
 8     <input type="button" value=http://www.mamicode.com/"全选"  onclick="CheckAll();"/>
 9     <input type="button" value=http://www.mamicode.com/"取消" onclick="CancelAll();"/>
10     <input type="button" value=http://www.mamicode.com/"反选" onclick="ReverseCheck();"/>
11 
12     <table border="1" >
13         <thead>
14 
15         </thead>
16         <tbody id="tb">
17             <tr>
18                 <td><input type="checkbox" /></td>
19                 <td>111</td>
20                 <td>222</td>
21             </tr>
22             <tr>
23                 <td><input type="checkbox" /></td>
24                 <td>111</td>
25                 <td>222</td>
26             </tr>
27             <tr>
28                 <td><input type="checkbox" /></td>
29                 <td>111</td>
30                 <td>222</td>
31             </tr>
32             <tr>
33                 <td><input type="checkbox" /></td>
34                 <td>111</td>
35                 <td>222</td>
36             </tr>
37         </tbody>
38     </table>
39     <script>
40         function CheckAll(ths){
41             var tb = document.getElementById(tb);
42             var trs = tb.childNodes;
43             for(var i =0; i<trs.length; i++){
44 
45                 var current_tr = trs[i];
46                 if(current_tr.nodeType==1){
47                     var inp = current_tr.firstElementChild.getElementsByTagName(input)[0];
48                     inp.checked = true;
49                 }
50             }
51         }
52 
53         function CancelAll(ths){
54             var tb = document.getElementById(tb);
55             var trs = tb.childNodes;
56             for(var i =0; i<trs.length; i++){
57 
58                 var current_tr = trs[i];
59                 if(current_tr.nodeType==1){
60                     var inp = current_tr.firstElementChild.getElementsByTagName(input)[0];
61                     inp.checked = false;
62                 }
63             }
64         }
65 
66         function ReverseCheck(ths){
67             var tb = document.getElementById(tb);
68             var trs = tb.childNodes;
69             for(var i =0; i<trs.length; i++){
70                 var current_tr = trs[i];
71                 if(current_tr.nodeType==1){
72                     var inp = current_tr.firstElementChild.getElementsByTagName(input)[0];
73                     if(inp.checked){
74                         inp.checked = false;
75                     }else{
76                         inp.checked = true;
77                     }
78                 }
79             }
80         }
81 
82     </script>
83 </body>
84 </html>
Demo

 

 

 3、class操作

  className        //获取所有类名

  calssList.remove(cls)  //删除指定类

  classList.add(cls)    //添加类

 4、标签操作

  a、创建标签

  //方式一

  var tag = document.createElement(‘a‘)

  tag.innerText = "Lyon"

  tag.className = "c1"

  tag.href = "http://www.cnblogs.com/wupeiqi"

  //方式二

  var tag = "<a class="c1"

  href = "http://ww.cnblogs.com/wupeiqi">wupeiqi</a>

  b、标签操作

  //方式一

  var boj = "<input type = "text" />";

  xxx.insertAdjacentHTML("beforeEnd",obj);

  xxx.insertAdjacentElement("afterBegin",docment.createElement(‘p‘))

 

  //注意:第一个参数只能是"beforeBegin"、"afterBengin"、"beforeEnd"、"afterEnd"

  //方式二

  var tag = focument.createElement(‘a‘)

  xxx.appendChild(tag)

  xxx.insertBefroe(tag,xxx[1])

 

 5、样式操作

  var obj = document.getElementById(‘i1‘)

  obj.style.fontSize =  "32px";

  obj.style.backgroundColor = "red";

  

技术分享
 1     <input onfocus="Focus(this);" onblur="Blur(this);" id="search" value=http://www.mamicode.com/"请输入关键字" style="color: gray;" />
 2 
 3     <script>
 4         function Focus(ths){
 5             ths.style.color = "black";
 6             if(ths.value =http://www.mamicode.com/= 请输入关键字 || ths.value.trim() == ""){
 7 
 8                 ths.value = http://www.mamicode.com/"";
 9             }
10         }
11 
12         function Blur(ths){
13             if(ths.value.trim() == ""){
14                 ths.value = http://www.mamicode.com/请输入关键字;
15                 ths.style.color = gray;
16             }else{
17                 ths.style.color = "black";
18             }
19         }
20     </script>
Demo

 

 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

  夫定位标签

  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

*/

技术分享
 1 <!DOCTYPE html>
 2 <html>
 3 <head lang="en">
 4     <meta charset="UTF-8">
 5     <title></title>
 6 </head>
 7 <body style="margin: 0;">
 8     <div style="height: 900px;">
 9 
10     </div>
11     <div style="padding: 10px;">
12         <div id="i1" style="height:190px;padding: 2px;border: 1px solid red;margin: 8px;">
13                 <p>asdf</p>
14                 <p>asdf</p>
15                 <p>asdf</p>
16                 <p>asdf</p>
17                 <p>asdf</p>
18         </div>
19     </div>
20 
21     <script>
22         var i1 = document.getElementById(i1);
23 
24         console.log(i1.clientHeight); // 可见区域:height + padding
25         console.log(i1.clientTop);    // border高度
26         console.log(=====);
27         console.log(i1.offsetHeight); // 可见区域:height + padding + border
28         console.log(i1.offsetTop);    // 上级定位标签的高度
29         console.log(=====);
30         console.log(i1.scrollHeight);   //全文高:height + padding
31         console.log(i1.scrollTop);      // 滚动高度
32         console.log(=====);
33 
34     </script>
35 </body>
36 </html>
test

 

技术分享
  1 <!DOCTYPE html>
  2 <html>
  3 <head lang="en">
  4     <meta charset="UTF-8">
  5     <title></title>
  6 </head>
  7 <style>
  8 
  9     body{
 10         margin: 0px;
 11     }
 12     img {
 13         border: 0;
 14     }
 15     ul{
 16         padding: 0;
 17         margin: 0;
 18         list-style: none;
 19     }
 20     .clearfix:after {
 21         content: ".";
 22         display: block;
 23         height: 0;
 24         clear: both;
 25         visibility: hidden;
 26     }
 27 
 28     .wrap{
 29         width: 980px;
 30         margin: 0 auto;
 31     }
 32 
 33     .pg-header{
 34         background-color: #303a40;
 35         -webkit-box-shadow: 0 2px 5px rgba(0,0,0,.2);
 36         -moz-box-shadow: 0 2px 5px rgba(0,0,0,.2);
 37         box-shadow: 0 2px 5px rgba(0,0,0,.2);
 38     }
 39     .pg-header .logo{
 40         float: left;
 41         padding:5px 10px 5px 0px;
 42     }
 43     .pg-header .logo img{
 44         vertical-align: middle;
 45         width: 110px;
 46         height: 40px;
 47 
 48     }
 49     .pg-header .nav{
 50         line-height: 50px;
 51     }
 52     .pg-header .nav ul li{
 53         float: left;
 54     }
 55     .pg-header .nav ul li a{
 56         display: block;
 57         color: #ccc;
 58         padding: 0 20px;
 59         text-decoration: none;
 60         font-size: 14px;
 61     }
 62     .pg-header .nav ul li a:hover{
 63         color: #fff;
 64         background-color: #425a66;
 65     }
 66     .pg-body{
 67 
 68     }
 69     .pg-body .catalog{
 70         position: absolute;
 71         top:60px;
 72         width: 200px;
 73         background-color: #fafafa;
 74         bottom: 0px;
 75     }
 76     .pg-body .catalog.fixed{
 77         position: fixed;
 78         top:10px;
 79     }
 80 
 81     .pg-body .catalog .catalog-item.active{
 82         color: #fff;
 83         background-color: #425a66;
 84     }
 85 
 86     .pg-body .content{
 87         position: absolute;
 88         top:60px;
 89         width: 700px;
 90         margin-left: 210px;
 91         background-color: #fafafa;
 92         overflow: auto;
 93     }
 94     .pg-body .content .section{
 95         height: 500px;
 96     }
 97 </style>
 98 <body onscroll="ScrollEvent();">
 99 <div class="pg-header">
100     <div class="wrap clearfix">
101         <div class="logo">
102             <a href=http://www.mamicode.com/"#">
103                 <img src=http://www.mamicode.com/"http://core.pc.lietou-static.com/revs/images/common/logo_7012c4a4.pn">
104             </a>
105         </div>
106         <div class="nav">
107             <ul>
108                 <li>
109                     <a  href=http://www.mamicode.com/"#">首页</a>
110                 </li>
111                 <li>
112                     <a  href=http://www.mamicode.com/"#">功能一</a>
113                 </li>
114                 <li>
115                     <a  href=http://www.mamicode.com/"#">功能二</a>
116                 </li>
117             </ul>
118         </div>
119 
120     </div>
121 </div>
122 <div class="pg-body">
123     <div class="wrap">
124         <div class="catalog">
125             <div class="catalog-item" auto-to="function1"><a>第1张</a></div>
126             <div class="catalog-item" auto-to="function2"><a>第2张</a></div>
127             <div class="catalog-item" auto-to="function3"><a>第3张</a></div>
128         </div>
129         <div class="content">
130             <div menu="function1" class="section">
131                 <h1>第一章</h1>
132             </div>
133             <div menu="function2" class="section">
134                 <h1>第二章</h1>
135             </div>
136             <div menu="function3" class="section">
137                 <h1>第三章</h1>
138             </div>
139         </div>
140     </div>
141 
142 </div>
143     <script>
144         function ScrollEvent(){
145             var bodyScrollTop = document.body.scrollTop;
146             if(bodyScrollTop>50){
147                 document.getElementsByClassName(catalog)[0].classList.add(fixed);
148             }else{
149                 document.getElementsByClassName(catalog)[0].classList.remove(fixed);
150             }
151 
152         }
153     </script>
154 </body>
155 </html>
Demo - 滚动固定

 

技术分享
  1 <!DOCTYPE html>
  2 <html>
  3 <head lang="en">
  4     <meta charset="UTF-8">
  5     <title></title>
  6 </head>
  7 <style>
  8 
  9     body{
 10         margin: 0px;
 11     }
 12     img {
 13         border: 0;
 14     }
 15     ul{
 16         padding: 0;
 17         margin: 0;
 18         list-style: none;
 19     }
 20     h1{
 21         padding: 0;
 22         margin: 0;
 23     }
 24     .clearfix:after {
 25         content: ".";
 26         display: block;
 27         height: 0;
 28         clear: both;
 29         visibility: hidden;
 30     }
 31 
 32     .wrap{
 33         width: 980px;
 34         margin: 0 auto;
 35     }
 36 
 37     .pg-header{
 38         background-color: #303a40;
 39         -webkit-box-shadow: 0 2px 5px rgba(0,0,0,.2);
 40         -moz-box-shadow: 0 2px 5px rgba(0,0,0,.2);
 41         box-shadow: 0 2px 5px rgba(0,0,0,.2);
 42     }
 43     .pg-header .logo{
 44         float: left;
 45         padding:5px 10px 5px 0px;
 46     }
 47     .pg-header .logo img{
 48         vertical-align: middle;
 49         width: 110px;
 50         height: 40px;
 51 
 52     }
 53     .pg-header .nav{
 54         line-height: 50px;
 55     }
 56     .pg-header .nav ul li{
 57         float: left;
 58     }
 59     .pg-header .nav ul li a{
 60         display: block;
 61         color: #ccc;
 62         padding: 0 20px;
 63         text-decoration: none;
 64         font-size: 14px;
 65     }
 66     .pg-header .nav ul li a:hover{
 67         color: #fff;
 68         background-color: #425a66;
 69     }
 70     .pg-body{
 71 
 72     }
 73     .pg-body .catalog{
 74         position: absolute;
 75         top:60px;
 76         width: 200px;
 77         background-color: #fafafa;
 78         bottom: 0px;
 79     }
 80     .pg-body .catalog.fixed{
 81         position: fixed;
 82         top:10px;
 83     }
 84 
 85     .pg-body .catalog .catalog-item.active{
 86         color: #fff;
 87         background-color: #425a66;
 88     }
 89 
 90     .pg-body .content{
 91         position: absolute;
 92         top:60px;
 93         width: 700px;
 94         margin-left: 210px;
 95         background-color: #fafafa;
 96         overflow: auto;
 97     }
 98     .pg-body .content .section{
 99         height: 500px;
100         border: 1px solid red;
101     }
102 </style>
103 <body onscroll="ScrollEvent();">
104 <div class="pg-header">
105     <div class="wrap clearfix">
106         <div class="logo">
107             <a href=http://www.mamicode.com/"#">
108                 <img src=http://www.mamicode.com/"http://core.pc.lietou-static.com/revs/images/common/logo_7012c4a4.pn">
109             </a>
110         </div>
111         <div class="nav">
112             <ul>
113                 <li>
114                     <a  href=http://www.mamicode.com/"#">首页</a>
115                 </li>
116                 <li>
117                     <a  href=http://www.mamicode.com/"#">功能一</a>
118                 </li>
119                 <li>
120                     <a  href=http://www.mamicode.com/"#">功能二</a>
121                 </li>
122             </ul>
123         </div>
124 
125     </div>
126 </div>
127 <div class="pg-body">
128     <div class="wrap">
129         <div class="catalog" id="catalog">
130             <div class="catalog-item" auto-to="function1"><a>第1张</a></div>
131             <div class="catalog-item" auto-to="function2"><a>第2张</a></div>
132             <div class="catalog-item" auto-to="function3"><a>第3张</a></div>
133         </div>
134         <div class="content" id="content">
135             <div menu="function1" class="section">
136                 <h1>第一章</h1>
137             </div>
138             <div menu="function2" class="section">
139                 <h1>第二章</h1>
140             </div>
141             <div menu="function3" class="section">
142                 <h1>第三章</h1>
143             </div>
144         </div>
145     </div>
146 
147 </div>
148     <script>
149         function ScrollEvent(){
150             var bodyScrollTop = document.body.scrollTop;
151             if(bodyScrollTop>50){
152                 document.getElementsByClassName(catalog)[0].classList.add(fixed);
153             }else{
154                 document.getElementsByClassName(catalog)[0].classList.remove(fixed);
155             }
156 
157             var content = document.getElementById(content);
158             var sections = content.children;
159             for(var i=0;i<sections.length;i++){
160                 var current_section = sections[i];
161 
162                 // 当前标签距离顶部绝对高度
163                 var scOffTop = current_section.offsetTop + 60;
164 
165                 // 当前标签距离顶部,相对高度
166                 var offTop = scOffTop - bodyScrollTop;
167 
168                 // 当前标签高度
169                 var height = current_section.scrollHeight;
170 
171                 if(offTop<0 && -offTop < height){
172                     // 当前标签添加active
173                     // 其他移除 active
174                     var menus = document.getElementById(catalog).children;
175                     var current_menu = menus[i];
176                     current_menu.classList.add(active);
177                     for(var j=0;j<menus.length;j++){
178                         if(menus[j] == current_menu){
179 
180                         }else{
181                             menus[j].classList.remove(active);
182                         }
183                     }
184                     break;
185                 }
186 
187             }
188 
189 
190         }
191     </script>
192 </body>
193 </html>
Demo - 滚动菜单

 

技术分享
  1 <!DOCTYPE html>
  2 <html>
  3 <head lang="en">
  4     <meta charset="UTF-8">
  5     <title></title>
  6 </head>
  7 <style>
  8 
  9     body{
 10         margin: 0px;
 11     }
 12     img {
 13         border: 0;
 14     }
 15     ul{
 16         padding: 0;
 17         margin: 0;
 18         list-style: none;
 19     }
 20     h1{
 21         padding: 0;
 22         margin: 0;
 23     }
 24     .clearfix:after {
 25         content: ".";
 26         display: block;
 27         height: 0;
 28         clear: both;
 29         visibility: hidden;
 30     }
 31 
 32     .wrap{
 33         width: 980px;
 34         margin: 0 auto;
 35     }
 36 
 37     .pg-header{
 38         background-color: #303a40;
 39         -webkit-box-shadow: 0 2px 5px rgba(0,0,0,.2);
 40         -moz-box-shadow: 0 2px 5px rgba(0,0,0,.2);
 41         box-shadow: 0 2px 5px rgba(0,0,0,.2);
 42     }
 43     .pg-header .logo{
 44         float: left;
 45         padding:5px 10px 5px 0px;
 46     }
 47     .pg-header .logo img{
 48         vertical-align: middle;
 49         width: 110px;
 50         height: 40px;
 51 
 52     }
 53     .pg-header .nav{
 54         line-height: 50px;
 55     }
 56     .pg-header .nav ul li{
 57         float: left;
 58     }
 59     .pg-header .nav ul li a{
 60         display: block;
 61         color: #ccc;
 62         padding: 0 20px;
 63         text-decoration: none;
 64         font-size: 14px;
 65     }
 66     .pg-header .nav ul li a:hover{
 67         color: #fff;
 68         background-color: #425a66;
 69     }
 70     .pg-body{
 71 
 72     }
 73     .pg-body .catalog{
 74         position: absolute;
 75         top:60px;
 76         width: 200px;
 77         background-color: #fafafa;
 78         bottom: 0px;
 79     }
 80     .pg-body .catalog.fixed{
 81         position: fixed;
 82         top:10px;
 83     }
 84 
 85     .pg-body .catalog .catalog-item.active{
 86         color: #fff;
 87         background-color: #425a66;
 88     }
 89 
 90     .pg-body .content{
 91         position: absolute;
 92         top:60px;
 93         width: 700px;
 94         margin-left: 210px;
 95         background-color: #fafafa;
 96         overflow: auto;
 97     }
 98     .pg-body .content .section{
 99         height: 500px;
100         border: 1px solid red;
101     }
102 </style>
103 <body onscroll="ScrollEvent();">
104 <div class="pg-header">
105     <div class="wrap clearfix">
106         <div class="logo">
107             <a href=http://www.mamicode.com/"#">
108                 <img src=http://www.mamicode.com/"http://core.pc.lietou-static.com/revs/images/common/logo_7012c4a4.pn">
109             </a>
110         </div>
111         <div class="nav">
112             <ul>
113                 <li>
114                     <a  href=http://www.mamicode.com/"#">首页</a>
115                 </li>
116                 <li>
117                     <a  href=http://www.mamicode.com/"#">功能一</a>
118                 </li>
119                 <li>
120                     <a  href=http://www.mamicode.com/"#">功能二</a>
121                 </li>
122             </ul>
123         </div>
124 
125     </div>
126 </div>
127 <div class="pg-body">
128     <div class="wrap">
129         <div class="catalog" id="catalog">
130             <div class="catalog-item" auto-to="function1"><a>第1张</a></div>
131             <div class="catalog-item" auto-to="function2"><a>第2张</a></div>
132             <div class="catalog-item" auto-to="function3"><a>第3张</a></div>
133         </div>
134         <div class="content" id="content">
135             <div menu="function1" class="section">
136                 <h1>第一章</h1>
137             </div>
138             <div menu="function2" class="section">
139                 <h1>第二章</h1>
140             </div>
141             <div menu="function3" class="section" style="height: 200px;">
142                 <h1>第三章</h1>
143             </div>
144         </div>
145     </div>
146 
147 </div>
148     <script>
149         function ScrollEvent(){
150             var bodyScrollTop = document.body.scrollTop;
151             if(bodyScrollTop>50){
152                 document.getElementsByClassName(catalog)[0].classList.add(fixed);
153             }else{
154                 document.getElementsByClassName(catalog)[0].classList.remove(fixed);
155             }
156 
157             var content = document.getElementById(content);
158             var sections = content.children;
159             for(var i=0;i<sections.length;i++){
160                 var current_section = sections[i];
161 
162                 // 当前标签距离顶部绝对高度
163                 var scOffTop = current_section.offsetTop + 60;
164 
165                 // 当前标签距离顶部,相对高度
166                 var offTop = scOffTop - bodyScrollTop;
167 
168                 // 当前标签高度
169                 var height = current_section.scrollHeight;
170 
171                 if(offTop<0 && -offTop < height){
172                     // 当前标签添加active
173                     // 其他移除 active
174 
175                     // 如果已经到底部,现实第三个菜单
176                     // 文档高度 = 滚动高度 + 视口高度
177 
178                     var a = document.getElementsByClassName(content)[0].offsetHeight + 60;
179                     var b = bodyScrollTop + document.documentElement.clientHeight;
180                     console.log(a+60,b);
181                     if(a == b){
182                         var menus = document.getElementById(catalog).children;
183                         var current_menu = document.getElementById(catalog).lastElementChild;
184                         current_menu.classList.add(active);
185                         for(var j=0;j<menus.length;j++){
186                             if(menus[j] == current_menu){
187 
188                             }else{
189                                 menus[j].classList.remove(active);
190                             }
191                         }
192                     }else{
193                         var menus = document.getElementById(catalog).children;
194                         var current_menu = menus[i];
195                         current_menu.classList.add(active);
196                         for(var j=0;j<menus.length;j++){
197                             if(menus[j] == current_menu){
198 
199                             }else{
200                                 menus[j].classList.remove(active);
201                             }
202                         }
203                     }
204 
205 
206 
207 
208                     break;
209                 }
210 
211             }
212 
213 
214         }
215     </script>
216 </body>
217 </html>
Demo - 滚动高度

 

  7、提交表单

  document.getElementById(‘form‘).submit()

 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 = "http://www.mamicode.com/url"   重定向

  location.reload()      重新加载

 

  //定时器

  setInterval        多次定时器

  clearInterval        清楚多次定时器

  setTimeout        单次定时器

  clearTimeout        清楚单次定时器

三、事件

 

技术分享

  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:

  

技术分享
 1 <!DOCTYPE html>
 2 <html>
 3     <head>
 4         <meta charset=utf-8 />
 5         <title></title>
 6         
 7         <style>
 8             .gray{
 9                 color:gray;
10             }
11             .black{
12                 color:black;
13             }
14         </style>
15         <script type="text/javascript">
16             function Enter(){
17                var id= document.getElementById("tip")
18                id.className = black;
19                if(id.value=http://www.mamicode.com/=请输入关键字||id.value.trim()==‘‘){
20                     id.value = http://www.mamicode.com/‘‘
21                }
22             }
23             function Leave(){
24                 var id= document.getElementById("tip")
25                 var val = id.value;
26                 if(val.length==0||id.value.trim()==‘‘){
27                     id.value = http://www.mamicode.com/请输入关键字
28                     id.className = gray;
29                 }else{
30                     id.className = black;
31                 }
32             }
33         </script>
34     </head>
35     <body>
36         <input type=text class=gray id=tip value=http://www.mamicode.com/请输入关键字 onfocus=Enter();  onblur=Leave();/>
37     </body>
38 </html>
搜索框

 

技术分享
 1 <!DOCTYPE html>
 2 <html>
 3     <head>
 4         <meta charset=utf-8 >
 5         <title>欢迎blue shit莅临指导&nbsp;&nbsp;</title>
 6         <script type=text/javascript>
 7             function Go(){
 8                 var content = document.title;
 9                 var firstChar = content.charAt(0)
10                 var sub = content.substring(1,content.length)
11                 document.title = sub + firstChar;
12             }
13             setInterval(Go(),1000);
14         </script>
15     </head>
16     <body>    
17     </body>
18 </html>
跑马灯

 

 

 

 

 

 

 

注:本文仅为学习笔记、摘要。

详细来源:http://www.cnblogs.com/wupeiqi/articles/5643298.html

 

Python全栈开发,Day17 - DOM