CanvasRenderingContext2D.rect()

The CanvasRenderingContext2D.rect() method of the Canvas 2D API creates a path for a rectangle at position (x, y) with a size that is determined by width and height. Those four points are connected by straight lines and the sub-path is marked as closed, so that you can fill or stroke this rectangle.

Syntax

JavaScript
void <var>ctx.rect(x, y, width, height);</var>

Parameters

x
The x axis of the coordinate for the rectangle starting point.
y
The y axis of the coordinate for the rectangle starting point.
width
The rectangle's width.
height
The rectangle's height.

Examples

Using the rect method

This is just a simple code snippet which uses the rect method to create a path. To actually draw that path onto the canvas, you can use the fill() or stroke() method. See also the fillRect() and strokeRect() methods, which can do this in one step.

HTML

HTML
<canvas id="canvas"></canvas>

JavaScript

JavaScript
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
ctx.rect(10, 10, 100, 100);
ctx.fill();

Edit the code below and see your changes update live in the canvas:

Playable code
HTML
<canvas id="canvas" width="400" height="200" class="playable-canvas"></canvas>
<div class="playable-buttons">
  <input id="edit" type="button" value="Edit" />
  <input id="reset" type="button" value="Reset" />
</div>
<textarea id="code" class="playable-code">
ctx.rect(10, 10, 100, 100);
ctx.fill();</textarea>
JavaScript
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var textarea = document.getElementById("code");
var reset = document.getElementById("reset");
var edit = document.getElementById("edit");
var code = textarea.value;

function drawCanvas() {
  ctx.clearRect(0, 0, canvas.width, canvas.height);
  eval(textarea.value);
}

reset.addEventListener("click", function() {
  textarea.value = code;
  drawCanvas();
});

edit.addEventListener("click", function() {
  textarea.focus();
})

textarea.addEventListener("input", drawCanvas);
window.addEventListener("load", drawCanvas);

Specifications

Specification Status Comment
WHATWG HTML Living Standard
The definition of 'CanvasRenderingContext2D.rect' in that specification.
Living Standard  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

See also

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/canvasrenderingcontext2d/rect

API Canvas CanvasRenderingContext2D Method Reference Référence