svg
svg: scalable vector graphics,可缩放的矢量图
- 该图片使用代码书写而成
- 缩放不会失真
- 内容轻量
怎么使用
svg 可以嵌入浏览器,也可以单独成为一个文件
xml 语言,svg 使用该语言定义
html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>Document</title>
<style>
img,
embed,
object,
iframe {
width: 100px;
height: 100px;
}
p {
width: 100px;
height: 100px;
background: url("imgs/weixin.svg") no-repeat center/cover;
}
</style>
</head>
<body>
<img src="imgs/weixin.svg" alt="" />
<p></p>
<embed src="imgs/weixin.svg" type="image/svg+xml" />
<object data="imgs/weixin.svg" type="image/svg+xml"></object>
<iframe src="imgs/weixin.svg"></iframe>
</body>
</html>书写 svg 代码
xml 必须由 svg 标签包裹
矩形:rect
xml
<svg style="background:#ccc;" width="500" height="1000" xmlns="http://www.w3.org/2000/svg">
<rect width="100" height="100" x="100" y="100" fill="red" stroke="#000" stroke-width="5" />
</svg>圆形:circle
xml
<circle cx="200" cy="400" r="50" fill="transparent" stroke="#000" stroke-width="5"/>椭圆:ellipse
xml
<ellipse rx="80" ry="30" cx="200" cy="500" fill="red" stroke="#000" stroke-width="5" />线条:line
xml
<line x1="10" y1="10" x2="300" y2="30" stroke="#000" stroke-width="3" />折线:polyline
xml
<polyline points="300,100,350,100,350,150,400,150,400,200" fill="red" stroke="#000" stroke-width="3">多边形:polygon
xml
<polygon points="300,300, 400, 400, 300, 500" fill="none" stroke="#000" stroke-width="3" />路径:path
xml
<path d="M150 600 L300 600 L300 800 L150 800 Z" fill="red" style="stroke:#000; stroke-width:5" />
<path d="M300 300 A150 150 0 0 0 450 150" fill="none" style="stroke:#000; stroke-width:3" />M = moveto L = lineto H = horizontal lineto V = vertical lineto C = curveto S = smooth curveto Q = quadratic Belzier curve T = smooth quadratic Belzier curveto A = elliptical Arc
A 半径 1
半径 2
顺时针旋转角度
小弧(0)或大弧(1)
顺时针(1)逆时针(0)
Z = closepath
例子
画太极图
xml
<svg xmlns="http://www.w3.org/2000/svg" width="500" height="500" style="background:#ccc">
<path fill="#000" d="M250 50 A100 100 0 0 1 250 250 A100 100 0 0 0 250 450 A200 200 0 0 1 250 50"/>
<path fill="#fff" d="M250 50 A100 100 0 0 1 250 250 A100 100 0 0 0 250 450 A200 200 0 0 0 250 50"/>
<circle cx="250" cy="150" r="30" fill="#fff"/>
<circle cx="250" cy="350" r="30" fill="#000"/>
</svg>