typescript重写canvas --11.文字大小

1.使用 canvas 文字大小

<!DOCTYPE HTML>
<html>
<head>
  <meta charset="utf-8" />
</head>
<body>
<canvas id="myCanvas" width="600" height="400">
你的浏览器不支持HTML5
</canvas>
<script type="text/javascript">
var canvas=document.getElementById("myCanvas");
var context=canvas.getContext("2d");  
    
context.beginPath();
//设定文字大小为30px
context.font="30px Arial";
context.fillText("Hello World",100,50);

context.beginPath();
//设定文字大小为50px
context.font="50px Arial";
context.fillText("Hello World",100,150);

context.beginPath();
//设定文字大小为100px
context.font="70px Arial";
context.fillText("Hello World",100,250);
    
</script>
</body>
</html>

显示效果如下

11.png

2.typescript重写canvas --文字大小

html文件

<!DOCTYPE HTML>
<html>
<body>
<canvas id="myCanvas" width="600" height="400">
你的浏览器不支持HTML5
</canvas>
<script src="./js/11.js"></script>

</body>
</html>

ts文件

const canvas=<HTMLCanvasElement>document.getElementById("myCanvas")
const context=canvas.getContext("2d") 
if (context){
context.beginPath();
//设定文字大小为30px
context.font="30px Arial";
context.fillText("Hello World",100,50);

context.beginPath();
//设定文字大小为50px
context.font="50px Arial";
context.fillText("Hello World",100,150);

context.beginPath();
//设定文字大小为100px
context.font="70px Arial";
context.fillText("Hello World",100,250);
}

生成的js文件

"use strict";
const canvas = document.getElementById("myCanvas");
const context = canvas.getContext("2d");
if (context) {
context.beginPath();
//设定文字大小为30px
context.font="30px Arial";
context.fillText("Hello World",100,50);

context.beginPath();
//设定文字大小为50px
context.font="50px Arial";
context.fillText("Hello World",100,150);

context.beginPath();
//设定文字大小为100px
context.font="70px Arial";
context.fillText("Hello World",100,250);
}