Detailed explanation of JavaScript creative clock project
This article mainly brings you a JavaScript creative clock project. The editor thinks it’s pretty good, so I’ll share it with you now and give it as a reference. Let’s follow the editor to take a look, I hope it can help everyone.
1. Final effect display:
2. Project highlights
1. The code structure is clear
2. Can dynamically display the current time and date in real time
3. The interface is simple, beautiful and generous
4. Improve browser compatibility
3. Summary of knowledge points:
jQuery, native javascript, css3, h5
4. Explanation of important and difficult points
1. To obtain the rotation angle of each pointer
First of all, the following concepts must be clarified:
The clock pointer rotates 360 degrees in a circle
Hour hand:
There are 12 hours in total on the dial , rotate 30 degrees every hour;
Minute hand:
There are 60 small grids on the dial. Every minute the minute hand passes a small grid, it rotates 6 degrees;
Second hand:
There are 60 small grids on the dial. Every minute the second hand moves through a small grid, it also rotates 6 degrees;
(1) Obtaining the current time
For example (taking the hour hand rotation angle calculation as an example): For example, the current time is 9:28;
The hour hand should be between 9 and 10, However, only the hour can be obtained through the method, so it is necessary to obtain both the current hour and the current minute, so as to better determine the rotation angle of the hour hand, which is the following method:
(2) Obtaining the rotation angle
Since the hour hand rotates 30 degrees after every hour, the rotation angle of the hour hand is obtained as follows:
Similarly, the rotation angles of the minute hand and the second hand are as follows:
Minute hand:
Second hand:
In order to make the clock more accurate, it is accurate to milliseconds;
(3) Execution frequency, that is, second hand rotation frequency control
Adjust the execution time interval of the function to change the second hand rotation frequency.
5. Project areas to be optimized
1. The page is too concise and needs further optimization and improvement;
2. There is no time to draw the minutes and seconds on the clock when drawing;
6. Codes for each part of the project
1.HTML code
nbsp;html> <meta> <title>jQuery指针时钟(附带日期)</title> <!--引入外部css样式--> <link> <!--引入jQuery库文件--> <script></script> <!--引入外部js文件--> <script></script> <p> </p>
2.css code
* { margin:0; padding:0; } body { background:#f9f9f9; color:#000; font:15px Calibri, Arial, sans-serif; text-shadow:1px 2px 1px #FFFFFF; } a, a:visited { text-decoration:none; outline:none; color:#fff; } a:hover { text-decoration:underline; color:#ddd; } /*the footer (尾部)*/ footer { background:#444 url("../images/bg-footer.png") repeat; position:fixed; width:100%; height:70px; bottom:0; left:0; color:#fff; text-shadow:2px 2px #000; /*提高浏览器的兼容性*/ -moz-box-shadow:5px 1px 10px #000; -webkit-box-shadow:5px 1px 10px #000; box-shadow:5px 1px 10px #000; } footer h1 { font:25px/26px Acens; font-weight:normal; left:50%; margin:0px 0 0 150px; padding:25px 0; position:relative; width:400px; } footer a.orig, a.orig:visited { background:url("../images/demo2.png") no-repeat right top; border:none; text-decoration:none; color:#FCFCFC; font-size:14px; height:70px; left:50%; line-height:50px; margin:12px 0 0 -400px; position:absolute; top:0; width:250px; } /*styling for the clock(时钟样式)*/ #clock { position: relative; width: 600px; height: 600px; list-style: none; margin: 20px auto; background: url('../images/clock.png') no-repeat center; } #seconds, #minutes, #hours { position: absolute; width: 30px; height: 580px; left: 270px; } #date { position: absolute; top: 365px; color: #666; right: 140px; font-weight: bold; letter-spacing: 3px; font-family: "微软雅黑"; font-size: 30px; line-height: 36px; } #hours { background: url('../images/hands.png') no-repeat left; z-index: 1000; } #minutes { background: url('../images/hands.png') no-repeat center; width:25px; z-index: 2000; } #seconds { background: url('../images/hands.png') no-repeat right; z-index: 3000; }
3.js code
(1) You need to download a js reference package (you will know it by Baidu or Google)
(2) js code
$(document).ready(function () { //动态插入HTML代码,标记时钟 var clock = [ '
- ',
'
- ', '
- ', '
- ', '
- ', '
4. Some necessary picture materials (c will not be listed or displayed one by one here)
Notes:
1.Transform attribute
2.rotate() method
Related recommendations:
Use canvas to make clock implementation steps
Examples to explain JS+CSS to achieve rolling digital clock effect
The above is the detailed content of Detailed explanation of JavaScript creative clock project. For more information, please follow other related articles on the PHP Chinese website!

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

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.

WebStorm Mac version
Useful JavaScript development tools

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

Zend Studio 13.0.1
Powerful PHP integrated development environment