SVG 边框（stroke）

属性介绍

• stroke 边框（轮廓）颜色
• stroke-width 边框（轮廓）厚度
• stroke-linecap 开放路径的终结样式（或称为画笔线帽）
  
  • butt 无线帽
  • round 圆形的线帽
  • square 方形的线帽
• stroke-dasharray 定义一实线虚线长度数组，不断重复该样式

stroke

stroke指的是边框（轮廓）的颜色

<svg xmlns="http://www.w3.org/2000/svg" >
    <line x1="10" y1="10" x2="110" y2="10" stroke="red"/>
    <line x1="10" y1="10" x2="110" y2="40" stroke="green" />
    <line x1="10" y1="10" x2="110" y2="70" stroke="blue" />
svg>

stroke-width

边框（轮廓）厚度指的是，在fill区域边界处的径向宽度，即边界处向外stroke-width/2和边界处向内stroke-width/2的区域是线宽。

<svg xmlns="http://www.w3.org/2000/svg" width="200" height="200">
    <line x1="10" y1="30" x2="110" y2="30" stroke="red" stroke-width="30"/>
    <circle cx="10" cy="30" r="5" fill="purple" />
    <path d="M120,30 v15" fill="none" stroke="green" stroke-width="5"/>
    <path d="M130,15 v30" fill="none" stroke="blue" stroke-width="5"/>

    <circle cx="50" cy="100" r="30" stroke-width="30" fill="red" stroke="yellow" stroke-opacity="0.5"/>
    <line x1="50" x2="80" y1="100" y2="100" stroke-width="2" stroke="black"/>
svg>

stroke-linecap

stroke-linecap指的是线帽，即开放路径的终结样式，共3种：butt、round、square

MDN开发文档 https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/stroke-linecap

the stroke-linecap attribute specifies the shape to be used at the end of open subpaths when they are stroked.

As a presentation attribute, it also can be used as a property directly inside a CSS stylesheet

<svg xmlns="http://www.w3.org/2000/svg" width="150" height="150" >
    <line stroke-linecap="butt" x1="30" y1="30" x2="130" y2="30" stroke="black" stroke-width="20"/>
    <line stroke-linecap="round" x1="30" y1="60" x2="130" y2="60" stroke="black" stroke-width="20"/>
    <line stroke-linecap="square" x1="30" y1="90" x2="130" y2="90" stroke="black" stroke-width="20"/>
    <path d="M30,30 h100 M30,60 h100 M30,90 h100" stroke="red" stroke-width="5"/>
svg>

stroke-dasharray

stroke-dasharray定义了一个实线、虚线数组的长度数组，然后不断的重复该样式。

<svg xmlns="http://www.w3.org/2000/svg" version="1.1">
    <g fill="none" stroke="black" stroke-width="4">
        <path stroke-dasharray="5,5" d="M10 20 H250" />
        <path stroke-dasharray="10,10" d="M10 40 H250" />
        <path stroke-dasharray="20,10,5,5,5,10" d="M10 60 H250" />
    g>
svg>