rect（路徑命令）

Created: November-22, 2018

context.rect(leftX, topY, width, height)

給定左上角和寬度和高度的矩形。

StackOverflow 文件

<!doctype html>
<html>
<head>
<style>
    body{ background-color:white; }
    #canvas{border:1px solid red; }
</style>
<script>
window.onload=(function(){

    // get a reference to the canvas element and it's context
    var canvas=document.getElementById("canvas");
    var ctx=canvas.getContext("2d");

    // arguments
    var leftX=25;
    var topY=25;
    var width=40;
    var height=25;

    // A rectangle drawn using the "rect" command.
    ctx.beginPath();
    ctx.rect(leftX, topY, width, height);
    ctx.stroke();

}); // end window.onload
</script>
</head>
<body>
    <canvas id="canvas" width=200 height=150></canvas>
</body>
</html>

context.rect 是一個獨特的繪圖命令，因為它新增了斷開連線的矩形。

這些斷開連線的矩形不會通過線自動連線。

StackOverflow 文件

<!doctype html>
<html>
<head>
<style>
    body{ background-color:white; }
    #canvas{border:1px solid red; }
</style>
<script>
window.onload=(function(){

    // get a reference to the canvas element and it's context
    var canvas=document.getElementById("canvas");
    var ctx=canvas.getContext("2d");

    // arguments
    var leftX=25;
    var topY=25;
    var width=40;
    var height=25;

    // Multiple rectangles drawn using the "rect" command.
    ctx.beginPath();
    ctx.rect(leftX, topY, width, height);
    ctx.rect(leftX+50, topY+20, width, height);
    ctx.rect(leftX+100, topY+40, width, height);
    ctx.stroke();

}); // end window.onload
</script>
</head>
<body>
    <canvas id="canvas" width=200 height=150></canvas>
</body>
</html>