var clock=document.getElementById("clock ");
var cxt=clock.getContext("2d");
function drawNow(){
var now=new Date();
var hour=now.getHours();
var min=now.getMinutes();
var sec=now.getSeconds();
hour=hour>12?hour-12:hour;
hour=hour min/60;
//Dial (blue)
cxt.lineWidth=10;
cxt.strokeStyle="blue"
cxt.beginPath();
cxt.arc(250,250,200,0,360,false);
cxt.closePath();
cxt.stroke();
//Scale
//Time scale
for(var i=0;i cxt.save();
cxt.lineWidth=7;
cxt.strokeStyle="black";
cxt.translate(250,250);
cxt.rotate(i*30*Math. PI/180);//Rotation angle*Math.PI/180=radians
cxt.beginPath();
cxt.moveTo(0,-170);
cxt.lineTo(0,- 190);
cxt.closePath();
cxt.stroke();
cxt.restore();
}
//Score
for(var i=0 ;i cxt.save();
//Set the thickness of the sub-scales
cxt.lineWidth=5;
//Reset the canvas origin
cxt. translate(250,250);
//Set the rotation angle
cxt.rotate(i*6*Math.PI/180);
//Draw the minute hand scale
cxt.strokeStyle="black";
cxt.beginPath();
cxt.moveTo(0,-180);
cxt.lineTo(0,-190);
cxt.closePath();
cxt.stroke ();
cxt.restore();
}
//Hour hand
cxt.save();
// Set the hour hand style
cxt.lineWidth=7;
cxt.strokeStyle="black";
cxt.translate(250,250);
cxt.rotate(hour*30*Math.PI/180);
cxt.beginPath();
cxt .moveTo(0,-140);
cxt.lineTo(0,10);
cxt.closePath();
cxt.stroke();
cxt.restore();
//Minute hand
cxt.save();
cxt.lineWidth=5;
cxt.strokeStyle="black";
//Set the center of the minute hand canvas in different dimensions
cxt .translate(250,250);
cxt.rotate(min*6*Math.PI/180);
cxt.beginPath();
cxt.moveTo(0,-160);
cxt .lineTo(0,15);
cxt.closePath();
cxt.stroke()
cxt.restore();
//Second hand
cxt.save();
//Set the style of the second hand
//Color: red
cxt.strokeStyle="red";
cxt.lineWidth=3;
//Reset the origin
cxt.translate (250,250);
//Set the angle
//cxt.rotate(330*Math.PI/180);
cxt.rotate(sec*6*Math.PI/180);
cxt.beginPath();
cxt.moveTo(0,-170);
cxt.lineTo(0,20);
cxt.closePath();
cxt.stroke();
//Draw the intersection of hour hand, minute hand and second hand
cxt.beginPath();
cxt.arc(0,0,5,0,360,false);
cxt.closePath();
//Set fill
cxt.fillStyle="gray";
cxt.fill();
//cxt.strokeStyle="red";
cxt.stroke();
//Draw the small dot for the second hand
cxt.beginPath();
cxt.arc(0,-140,5,0,360,false);
cxt.closePath();
//Set the fill
cxt.fillStyle="gray";
cxt.fill();
//cxt.strokeStyle="red";
cxt.stroke(); p>
cxt.restore();
}
function drawClock(){
cxt.clearRect(0,0,500,500);
drawNow();
}
drawNow();
setInterval(drawClock, 1000);

H5 improves web user experience with multimedia support, offline storage and performance optimization. 1) Multimedia support: H5 and elements simplify development and improve user experience. 2) Offline storage: WebStorage and IndexedDB allow offline use to improve the experience. 3) Performance optimization: WebWorkers and elements optimize performance to reduce bandwidth consumption.

HTML5 code consists of tags, elements and attributes: 1. The tag defines the content type and is surrounded by angle brackets, such as. 2. Elements are composed of start tags, contents and end tags, such as contents. 3. Attributes define key-value pairs in the start tag, enhance functions, such as. These are the basic units for building web structure.

HTML5 is a key technology for building modern web pages, providing many new elements and features. 1. HTML5 introduces semantic elements such as, , etc., which enhances web page structure and SEO. 2. Support multimedia elements and embed media without plug-ins. 3. Forms enhance new input types and verification properties, simplifying the verification process. 4. Offer offline and local storage functions to improve web page performance and user experience.

Best practices for H5 code include: 1. Use correct DOCTYPE declarations and character encoding; 2. Use semantic tags; 3. Reduce HTTP requests; 4. Use asynchronous loading; 5. Optimize images. These practices can improve the efficiency, maintainability and user experience of web pages.

Web standards and technologies have evolved from HTML4, CSS2 and simple JavaScript to date and have undergone significant developments. 1) HTML5 introduces APIs such as Canvas and WebStorage, which enhances the complexity and interactivity of web applications. 2) CSS3 adds animation and transition functions to make the page more effective. 3) JavaScript improves development efficiency and code readability through modern syntax of Node.js and ES6, such as arrow functions and classes. These changes have promoted the development of performance optimization and best practices of web applications.

H5 is not just the abbreviation of HTML5, it represents a wider modern web development technology ecosystem: 1. H5 includes HTML5, CSS3, JavaScript and related APIs and technologies; 2. It provides a richer, interactive and smooth user experience, and can run seamlessly on multiple devices; 3. Using the H5 technology stack, you can create responsive web pages and complex interactive functions.

H5 and HTML5 refer to the same thing, namely HTML5. HTML5 is the fifth version of HTML, bringing new features such as semantic tags, multimedia support, canvas and graphics, offline storage and local storage, improving the expressiveness and interactivity of web pages.

H5referstoHTML5,apivotaltechnologyinwebdevelopment.1)HTML5introducesnewelementsandAPIsforrich,dynamicwebapplications.2)Itsupportsmultimediawithoutplugins,enhancinguserexperienceacrossdevices.3)SemanticelementsimprovecontentstructureandSEO.4)H5'srespo


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

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.

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

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

Atom editor mac version download
The most popular open source editor