返回到：Canvas API：CanvasRenderingContext2D
CanvasRenderingContext2D.strokeStyle 是 Canvas 2D API 描述画笔（绘制图形）颜色或者样式的属性。默认值是 #000 (black)。
语法
ctx.strokeStyle = color;
ctx.strokeStyle = gradient;
ctx.strokeStyle = pattern;选项
color
DOMString 字符串，可以转换成 CSS <color> 值。
gradient
CanvasGradient 对象（线性渐变或放射性渐变）。
pattern
CanvasPattern 对象（可重复的图片）。
示例
使用 strokeStyle 属性设置不同的颜色
这是一段简单的代码片段，使用 strokeStyle 属性设置不同的颜色。
HTML
<canvas id="canvas"></canvas>JavaScript
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
ctx.strokeStyle = "blue";
ctx.strokeRect(10, 10, 100, 100);修改下面的代码并在线查看 canvas 的变化：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="robots" content="noindex, nofollow">
<style>
body {
padding: 0;
margin: 0;
}
svg:not(:root) {
display: block;
}
.playable-code {
background-color: #f4f7f8;
border: none;
border-left: 6px solid #558abb;
border-width: medium medium medium 6px;
color: #4d4e53;
height: 100px;
width: 90%;
padding: 10px 10px 0;
}
.playable-canvas {
border: 1px solid #4d4e53;
border-radius: 2px;
}
.playable-buttons {
text-align: right;
width: 90%;
padding: 5px 10px 5px 26px;
}
</style>
<title>CanvasRenderingContext2D.strokeStyle | Web176教程www.web176.com</title>
</head>
<body>
<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.strokeStyle = "blue";
ctx.strokeRect(10, 10, 100, 100);</textarea>
<script>
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
ctx.strokeStyle = "blue";
ctx.strokeRect(10, 10, 100, 100);
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);
</script>
</body>
</html>strokeStyle 例子
这个例子使用 strokeStyle 属性改变图形轮廓线的颜色。我们使用 arc() 绘制圆形来代替正方形。
var ctx = document.getElementById('canvas').getContext('2d');
for (var i=0;i<6;i++){
for (var 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();
}
}
结果如下显示：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="robots" content="noindex, nofollow">
<style>
body {
padding: 0;
margin: 0;
}
svg:not(:root) {
display: block;
}
.playable-code {
background-color: #f4f7f8;
border: none;
border-left: 6px solid #558abb;
border-width: medium medium medium 6px;
color: #4d4e53;
height: 100px;
width: 90%;
padding: 10px 10px 0;
}
.playable-canvas {
border: 1px solid #4d4e53;
border-radius: 2px;
}
.playable-buttons {
text-align: right;
width: 90%;
padding: 5px 10px 5px 26px;
}
</style>
<title>CanvasRenderingContext2D.strokeStyle | Web176教程www.web176.com</title>
</head>
<body>
<canvas id="canvas" width="150" height="150"></canvas>
<script>
var ctx = document.getElementById('canvas').getContext('2d');
for (var i=0;i<6;i++){
for (var 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();
}
}
</script>
</body>
</html>返回到：Canvas API：CanvasRenderingContext2D
作者：terry，如若转载，请注明出处：https://www.web176.com/canvas_api/7971.html
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