CanvasRenderingContext2D: strokeStyle property
The CanvasRenderingContext2D.strokeStyle
property of the
Canvas 2D API specifies the color, gradient, or pattern to use for the strokes
(outlines) around shapes. The default is #000
(black).
Note: For more examples of stroke and fill styles, see Applying styles and color in the Canvas tutorial.
Value
One of the following:
color
gradient
-
A
CanvasGradient
object (a linear or radial gradient). pattern
-
A
CanvasPattern
object (a repeating image).
Examples
Changing the stroke color of a shape
This example applies a blue stroke color to a rectangle.
HTML
html
<canvas id="canvas"></canvas>
JavaScript
js
const canvas = document.getElementById("canvas");
const ctx = canvas.getContext("2d");
ctx.strokeStyle = "blue";
ctx.strokeRect(10, 10, 100, 100);
Result
Creating multiple stroke colors using loops
In this example, we use two for
loops and the
arc()
method to draw a grid of circles,
each having a different stroke color. To achieve this, we use the two variables
i
and j
to generate a unique RGB color for each circle, and
only modify the green and blue values. (The red channel has a fixed value.)
js
const ctx = document.getElementById("canvas").getContext("2d");
for (let i = 0; i < 6; i++) {
for (let j = 0; j < 6; j++) {
ctx.strokeStyle = `rgb(
0,
${Math.floor(255 - 42.5 * i)},
${Math.floor(255 - 42.5 * j)})`;
ctx.beginPath();
ctx.arc(12.5 + j * 25, 12.5 + i * 25, 10, 0, Math.PI * 2, true);
ctx.stroke();
}
}
The result looks like this:
Screenshot | Live sample |
---|---|
Specifications
Specification |
---|
HTML Standard # dom-context-2d-strokestyle-dev |
Browser compatibility
BCD tables only load in the browser
WebKit/Blink-specific note
In WebKit- and Blink-based browsers, the non-standard and deprecated method
ctx.setStrokeColor()
is implemented in addition to this property.
js
setStrokeColor(color);
setStrokeColor(color, alpha);
setStrokeColor(grayLevel);
setStrokeColor(grayLevel, alpha);
setStrokeColor(r, g, b, a);
setStrokeColor(c, m, y, k, a);
See also
- The interface defining this property:
CanvasRenderingContext2D
CanvasGradient
CanvasPattern