Found 8894 Articles for Front End Technology

Drawing an SVG file on an HTML5 canvas

Naveen Singh
Updated on 24-Nov-2023 01:25:51

1K+ Views

To draw HTML Image Elements on a canvas element, use the drawImage() method. This method defines an Image variable with src = "mySVG.svg", and use drawImage on load. var myImg = new Image(); myImg.onload = function() {    ctx.drawImage(myImg, 0, 0); } img.src = "http://www.example.com/files/sample.svg ";

How to change the playing speed of videos in HTML5?

Naveen Singh
Updated on 21-Nov-2023 21:00:26

2K+ Views

Use the playbackRate property sets the current playback speed of the audio/video. With that, the defaultPlaybackRate property sets the default playback speed of the audio/video. Change the playing speed of videos You can try to run the following code to change the playing speed of videos − /* play video thrice as fast */ document.querySelector('video').defaultPlaybackRate = 3.0; document.querySelector('video').play(); Play video twice as fast The following is to play the video twice as fast − /* play video twice as fast */ document.querySelector('video').playbackRate = 2;

Streaming a video file to an HTML5 video player with Node.js so that the video controls continue to work

Naveen Singh
Updated on 04-Mar-2020 05:25:44

213 Views

Use createReadStream to send the requested part to the client. The function call createReadStream() will give you a readable stream. ExampleThe following is the code −stream = fs.createReadStream(path); stream.on('open', function () {    res.writeHead(206,{       "Content-Range":"bytes " + begin + "-" + end + "/" +total, "Accept-Ranges":"bytes",          "Content-Length":chunksize, "Content-Type":"new/mp4"    });    stream.pipe(res); });

Drawing an image from a data URL to a HTML5 canvas

Naveen Singh
Updated on 04-Mar-2020 05:06:54

947 Views

If you have a data url, you can create an image to a canvas. This can be done as shown in the following code snippet −var myImg = new Image; myImg.src = strDataURI;The drawImage() method draws an image, canvas, or video onto the canvas. The drawImage() method can also draw parts of an image, and/or increase/reduce the image size.The code given below is also appropriate with the sequence - create the image, set the onload to use the new image, and then set the src −// load image from data url Var Obj = new Image(); Obj.onload = function() { ... Read More

How to properly use h1 in HTML5?

Naveen Singh
Updated on 04-Mar-2020 05:06:02

205 Views

 h1 is a heading and not a title. Youcan gives own heading element to each sectioning element. h1 cannot be the title. It can be the heading of that particular section of the page. Each article can have its own title. defines the most important heading. The first element is considered the label for the entire document. It is perfectly fine to use as many tags as your document calls for; that is one per sectioning root or content section. Use one set of tags per sectioning root or content section. There should always be an ... Read More

HTML5 canvas ctx.fillText won't do line breaks

Naveen Singh
Updated on 20-Nov-2023 11:39:18

1K+ Views

The fillText() method draws filled text on the canvas. If you want to break lines you can do this by splitting the text at the new lines and calling the filltext() multiple times. By doing so, you are splitting the text into lines and drawing each line separately.You can try to run the following code snippet − var c = $('#c')[0].getContext('2d'); c.font = '12px Courier'; alert(c); var str = 'first line second line...'; var a = 30; var b = 30; var lineheight = 15; var lines = str.split(''); for (var j = 0; j

Change text color based on a brightness of the covered background area in HTML?

Naveen Singh
Updated on 04-Mar-2020 05:03:50

142 Views

It is possible to change the textcolour depending on the average brightness of the covered pixels ofits parent's background color by using the following code snippet.var rgb = [255, 0, 0]; setInterval(display, 1000); function display() {    rgb[0] = Math.round(Math.random() * 255);    rgb[1] = Math.round(Math.random() * 255);    rgb[2] = Math.round(Math.random() * 255);        var d = Math.round(((parseInt(rgb[0]) * 299) + (parseInt(rgb[1]) * 587) +       (parseInt(rgb[2]) * 114)) / 1000);    // for foregound    var f = (d> 125) ? 'black' : 'white';       // for background   var b = 'rgb(' + rgb[0] + ',' + rgb[1] + ',' + rgb[2] + ')';   $('#box').css('color', f);   $('#box').css('background-color', b); } DemoThe following is the CSS −#box {    width: 300px;   height: 300px; }

Bootstrap dropdown closing when clicked in HTML

Naveen Singh
Updated on 04-Mar-2020 05:03:11

2K+ Views

As you may have seen, whenever you open a dropdown, and click anywhere else, the dropdown close. By using the below given code, the dropdown menu can be kept open after click−$('#myDropdown').on('hide.bs.dropdown', function () {    return false; });Another option is to handle the clickevent −The click event can also be handled byusing the following code. The event.stopPropagation() method stopsthe bubbling of an event to parent elements. It prevents any parentevent handlers from being executed −$('#myDropdown .dropdown-menu').on({    "click":function(e) {        e.stopPropagation();     } });

Client Checking file size using HTML5

Naveen Singh
Updated on 04-Mar-2020 05:02:06

297 Views

Before HTML5, the file size was checked with flash but now flash is avoided in web apps. Still the file size on the client side can be checked by inserting the below given code inside an event listener.if (typeofFileReader !== "undefined") {    // file[0] is file 1    var s = document.getElementById('myfile').files[0].size; }On file input change, the size will update. For that, use event listener,document.getElementById('input').onchange = function() {    // file[0] is file 1    var s = document.getElementById('input').files[0].size;    alert(s); }

How to save HTML Canvas as an Image with canvas.toDataURL()?

Naveen Singh
Updated on 04-Mar-2020 04:47:58

722 Views

Use toDataURL() method to get the image data URL of the canvas. It converts the drawing (canvas) into a64 bit encoded PNG URL.ExampleYou can try to run the following code to save the canvas as an image −                                  var canvas = document.getElementById('newCanvas');          var ctx = canvas.getContext('2d');          // draw any shape          ctx.beginPath();          ctx.moveTo(120, 50);          ctx.bezierCurveTo(130,100, 130, 250, 330, 150);          ctx.bezierCurveTo(350,180, 320, 180, 240, 150);          ctx.bezierCurveTo(320,150, 420, 120, 390, 100);          ctx.bezierCurveTo(130,40, 370, 30, 240, 50);          ctx.bezierCurveTo(220,7, 350, 20, 150, 50);          ctx.bezierCurveTo(250,5, 150, 20, 170, 80);          ctx.closePath();          ctx.lineWidth = 3;          ctx.fillStyle ='#F1F1F1';          ctx.fill();          ctx.stroke();          var dataURL =canvas.toDataURL();          

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