HTML5 Canvas 绘制矩形

在HTML5画布元素上最容易绘制的形状之一是矩形。您可以使用2D上下文函数fillRect()和进行操作strokeRect()。

<canvas id="ex1" width="500" height="150" style="border: 1px solid #cccccc;">    
HTML5 Canvas not supported    
</canvas>    
<script>       
var canvas  = document.getElementById("ex1");    
var context = canvas.getContext("2d");    
context.fillStyle = "#ff0000";    
context.fillRect(10,10, 100,100);    
context.strokeStyle = "#0000ff";    
context.strokeRect(30,20, 120,110);      
</script>

行宽 - lineWidth

您可以使用lineWidth2D上下文的属性设置描边矩形的线宽。方法如下：

<canvas id="ex4" width="500" height="150" style="border: 1px solid #cccccc;">    
HTML5 Canvas not supported    
</canvas>    
<script>       
var canvas  = document.getElementById("ex4");    
var context = canvas.getContext("2d");    
var x = 10;    
var y = 10;    
var width = 100;    
var height = 100;    
context.lineWidth = 4;    
context.strokeRect(x, y, width, height);      
</script>

矩形颜色

您可以使用 2D上下文的fillStyle或strokeStyle属性设置绘制矩形的颜色。这是第一个示例，这些设置以粗体显示:

<canvas id="ex5" width="500" height="150" style="border: 1px solid #cccccc;">    
HTML5 Canvas not supported    
</canvas>    
<script>       
var canvas  = document.getElementById("ex5");    
var context = canvas.getContext("2d");    
context.fillStyle = "#ff0000";    
context.fillRect(10,10, 100,100);    
context.strokeStyle = "#0000ff";    
context.strokeRect(30,20, 120,110);    
</script>

引用

菜鸟教程