CanvasRenderingContext2D.fillStyle - Web APIs 编辑

The CanvasRenderingContext2D.fillStyle property of the Canvas 2D API specifies the color, gradient, or pattern to use inside shapes. The default style is #000 (black).

For more examples of fill and stroke styles, see Applying styles and color in the Canvas tutorial.

Syntax

ctx.fillStyle = color;
ctx.fillStyle = gradient;
ctx.fillStyle = pattern;

Options

color
A DOMString parsed as CSS <color> value.
gradient
A CanvasGradient object (a linear or radial gradient).
pattern
A CanvasPattern object (a repeating image).

Examples

Changing the fill color of a shape

This example applies a blue fill color to a rectangle.

HTML

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

JavaScript

const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');

ctx.fillStyle = 'blue';
ctx.fillRect(10, 10, 100, 100);

Result

Creating multiple fill colors using loops

In this example, we use two for loops to draw a grid of rectangles, each having a different fill color. To achieve this, we use the two variables i and j to generate a unique RGB color for each square, and only modify the red and green values. (The blue channel has a fixed value.) By modifying the channels, you can generate all kinds of palettes.

<canvas id="canvas" width="150" height="150"></canvas>
const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');

for (let i = 0; i < 6; i++) {
  for (let j = 0; j < 6; j++) {
    ctx.fillStyle = `rgb(
        ${Math.floor(255 - 42.5 * i)},
        ${Math.floor(255 - 42.5 * j)},
        0)`;
    ctx.fillRect(j * 25, i * 25, 25, 25);
  }
}

The result looks like this:

ScreenshotLive sample

Specifications

SpecificationStatusComment
HTML Living Standard
The definition of 'CanvasRenderingContext2D.fillStyle' in that specification.
Living Standard 

Browser compatibility

BCD tables only load in the browser

In WebKit- and Blink-based browsers, the non-standard and deprecated method ctx.setFillColor() is implemented in addition to this property.

setFillColor(color, optional alpha);
setFillColor(grayLevel, optional alpha);
setFillColor(r, g, b, a);
setFillColor(c, m, y, k, a);

See also

如果你对这篇内容有疑问,欢迎到本站社区发帖提问 参与讨论,获取更多帮助,或者扫码二维码加入 Web 技术交流群。

扫码二维码加入Web技术交流群

发布评论

需要 登录 才能够评论, 你可以免费 注册 一个本站的账号。
列表为空,暂无数据

词条统计

浏览:57 次

字数:6399

最后编辑:6 年前

编辑次数:0 次

    我们使用 Cookies 和其他技术来定制您的体验包括您的登录状态等。通过阅读我们的 隐私政策 了解更多相关信息。 单击 接受 或继续使用网站,即表示您同意使用 Cookies 和您的相关数据。
    原文