HTML5 Canvas

HTML5 Canvas

What is HTML Canvas?

The HTML <canvas> element is used to draw graphics, on the fly, via JavaScript.

The <canvas> element is only a container for graphics. You must use JavaScript to actually draw the graphics.

Canvas has several methods for drawing paths, boxes, circles, text, and adding images.

Browser Support

The numbers in the table specify the first browser version that fully supports the<canvas> element.

Element<canvas>4.09.02.03.19.0

Canvas Examples

A canvas is a rectangular area on an HTML page. By default, a canvas has no border and no content.

The markup looks like this:

<canvas id="myCanvas"width="200" height="100"></canvas>

The HTML <canvas> element is used to draw graphics on a web page.

The graphic to the left is created with <canvas>. It shows four elements: a red rectangle, a gradient rectangle, a multicolor rectangle, and a multicolor text.

Note: Always specify an id attribute (to be referred to in a script), and a width and height attribute to define the size of the canvas. To add a border, use the styleattribute.

Here is an example of a basic, empty canvas:

Example

<canvas id="myCanvas"width="200" height="100"style="border:1px solid #000000;">

</canvas>

Draw a Tex

Example

var c = document.getElementById("myCanvas");

var ctx = c.getContext("2d");

ctx.font = "30px Arial";

ctx.fillText("Hello World", 10, 50);

Example

var c = document.getElementById("myCanvas");

var ctx = c.getContext("2d");

ctx.font = "30px Arial";

ctx.strokeText("Hello World", 10, 50);

Draw a Circle

Example

var c = document.getElementById("myCanvas");

var ctx = c.getContext("2d");

ctx.beginPath();

ctx.arc(95, 50, 40, 0, 2 * Math.PI);

ctx.stroke();

Draw a Line

Example

var c = document.getElementById("myCanvas");

var ctx = c.getContext("2d");

ctx.moveTo(0, 0);

ctx.lineTo(200, 100);

ctx.stroke();