


JS implements infinite web page folding menu (similar to tree menu) effect code_javascript skills
The example in this article describes the JS code to realize the effect of infinite web page folding menu (similar to tree menu). Share it with everyone for your reference. The details are as follows:
This is a super good web page folding menu, implemented in JavaScript. The folding menu is a common menu form that everyone sees. It can be widely used in management systems, the left side of the backend, and product lists. This folding menu has a bit of a tree menu. I believe that "infinite levels" will meet your requirements.
The screenshot of the running effect is as follows:
The online demo address is as follows:
http://demo.jb51.net/js/2015/js-unlimit-fade-in-out-tree-menu-codes/
The specific code is as follows:
<html> <head> <title>无限级折叠菜单JS版</title> <style> <!-- body,ul,h3 {margin:0px; padding:0px;} li {list-style-type:none;} body{ font-size:12px; color:#333; font-family: Simsun; line-height:15px; } a{text-decoration:none;color:#004285;border:none;} a:hover{text-decoration:none;color:#C33;} #menu { width:260px; margin:50px auto; padding:10px; border:#EEE 1px solid; } #menu h3 { font-size:12px; } #menu ul { background:url("images/ul-bg.gif") repeat-y 5px 0px; overflow:hidden; } #menu ul li { padding:5px 0 2px 15px; background:url("images/tree-ul-li.gif") no-repeat 5px -32px; } #menu ul li ul {display:none;} #menu ul li em { cursor:pointer; display:inline-block; width:15px; float:left; height:15px; margin-left:-14px; background:url("images/tree-ul-li.gif") no-repeat -32px 2px; } #menu ul li em.off { background-position: -17px -18px; } #menu ul li#end { background-color:#FFF; } #menu ul.off { display:block; } --> </style> </head> <body> <div id="menu"> <h3 id="无限级折叠菜单JavaScript版">无限级折叠菜单JavaScript版</h3> <ul> <li><em></em><a href='javascript:void(0);'>菜单_1_1</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_2_1</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_3_1</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_3_2</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_2_2</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_3_1</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_3_2</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> </ul> </li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_1_2</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_2_1</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_3_1</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_3_2</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_2_2</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_3_1</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_3_2</a> <ul> <li><em></em><a href='javascript:void(0);'>菜单_4_1</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> <li id='end'><em></em><a href='javascript:void(0);'>菜单_4_2</a> <ul> <li><a href='javascript:void(0);'>菜单_5_1</a></li> <li id='end'><a href='javascript:void(0);'>菜单_5_2</a></li> </ul> </li> </ul> </li> </ul> </li> </ul> </li> </ul> </div> <script type="text/javascript"> (function(e){ for(var _obj=document.getElementById(e.id).getElementsByTagName(e.tag),i=-1,em;em=_obj[++i];){ em.onclick = function(){ //onmouseover var ul = this.nextSibling; if(!ul){return false;} ul = ul.nextSibling; if(!ul){return false;} if(e.tag != 'a'){ ul = ul.nextSibling; if(!ul){return false;} } //a 标签控制 隐藏或删除该行 for(var _li=this.parentNode.parentNode.childNodes,n=-1,li;li=_li[++n];){ if(li.tagName=="LI"){ for(var _ul=li.childNodes,t=-1,$ul;$ul=_ul[++t];){ switch($ul.tagName){ case "UL": $ul.className = $ul!=ul?"" : ul.className?"":"off"; break; case "EM": $ul.className = $ul!=this?"" : this.className?"":"off"; break; } } } } } } })({id:'menu',tag:'em'}); </script> </body> </html>
I hope this article will be helpful to everyone’s JavaScript programming.

JavaScript's application in the real world includes front-end and back-end development. 1) Display front-end applications by building a TODO list application, involving DOM operations and event processing. 2) Build RESTfulAPI through Node.js and Express to demonstrate back-end applications.

The main uses of JavaScript in web development include client interaction, form verification and asynchronous communication. 1) Dynamic content update and user interaction through DOM operations; 2) Client verification is carried out before the user submits data to improve the user experience; 3) Refreshless communication with the server is achieved through AJAX technology.

Understanding how JavaScript engine works internally is important to developers because it helps write more efficient code and understand performance bottlenecks and optimization strategies. 1) The engine's workflow includes three stages: parsing, compiling and execution; 2) During the execution process, the engine will perform dynamic optimization, such as inline cache and hidden classes; 3) Best practices include avoiding global variables, optimizing loops, using const and lets, and avoiding excessive use of closures.

Python is more suitable for beginners, with a smooth learning curve and concise syntax; JavaScript is suitable for front-end development, with a steep learning curve and flexible syntax. 1. Python syntax is intuitive and suitable for data science and back-end development. 2. JavaScript is flexible and widely used in front-end and server-side programming.

Python and JavaScript have their own advantages and disadvantages in terms of community, libraries and resources. 1) The Python community is friendly and suitable for beginners, but the front-end development resources are not as rich as JavaScript. 2) Python is powerful in data science and machine learning libraries, while JavaScript is better in front-end development libraries and frameworks. 3) Both have rich learning resources, but Python is suitable for starting with official documents, while JavaScript is better with MDNWebDocs. The choice should be based on project needs and personal interests.

The shift from C/C to JavaScript requires adapting to dynamic typing, garbage collection and asynchronous programming. 1) C/C is a statically typed language that requires manual memory management, while JavaScript is dynamically typed and garbage collection is automatically processed. 2) C/C needs to be compiled into machine code, while JavaScript is an interpreted language. 3) JavaScript introduces concepts such as closures, prototype chains and Promise, which enhances flexibility and asynchronous programming capabilities.

Different JavaScript engines have different effects when parsing and executing JavaScript code, because the implementation principles and optimization strategies of each engine differ. 1. Lexical analysis: convert source code into lexical unit. 2. Grammar analysis: Generate an abstract syntax tree. 3. Optimization and compilation: Generate machine code through the JIT compiler. 4. Execute: Run the machine code. V8 engine optimizes through instant compilation and hidden class, SpiderMonkey uses a type inference system, resulting in different performance performance on the same code.

JavaScript's applications in the real world include server-side programming, mobile application development and Internet of Things control: 1. Server-side programming is realized through Node.js, suitable for high concurrent request processing. 2. Mobile application development is carried out through ReactNative and supports cross-platform deployment. 3. Used for IoT device control through Johnny-Five library, suitable for hardware interaction.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

Zend Studio 13.0.1
Powerful PHP integrated development environment

WebStorm Mac version
Useful JavaScript development tools

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.