<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Document</title></head><body> <canvas id="canvas" style="border: 1px #ddd solid;display: block;margin:0 auto"></canvas> <script> var tangram = [ {p:[{x:0,y:0},{x:800,y:0},{x:400,y:400}],color:"red"}, {p:[{x:0,y:0},{x:400,y:400},{x:0,y:800}],color:"blue"}, {p:[{x:800,y:0},{x:800,y:400},{x:600,y:600},{x:600,y:200}],color:"yellow"}, {p:[{x:600,y:200},{x:600,y:600},{x:400,y:400}],color:"green"}, {p:[{x:400,y:400},{x:600,y:600},{x:400,y:800},{x:200,y:600}],color:"pink"}, {p:[{x:200,y:600},{x:0,y:800},{x:400,y:800}],color:"orange"}, {p:[{x:800,y:400},{x:800,y:800},{x:400,y:800}],color:"purple"} ]; function draw(piece,cxt){ cxt.beginPath(); cxt.moveTo(piece.p[0].x , piece.p[0].y); for(var i=1;i<piece.p.length;i++){ cxt.lineTo(piece.p[i].x , piece.p[i].y); } cxt.closePath(); cxt.fillStyle = piece.color; cxt.fill(); } window.onload = function(){ var canvas = document.getElementById('canvas'); canvas.width = 800; canvas.height = 800; if(canvas.getContext('2d')){ var context = canvas.getContext('2d'); for(var i=0;i<tangram.length;i++){ draw(tangram[i],context) } }else{ alert('当前游览器不支持Canvas，请更换游览器后再试！'); } } </script></body><script>/* 总结 绘制七巧板 主要运用的js的for循环的巧妙 1.定义路径 trangram 2.第一层for，循环trangram[i] 3.函数draw,第二层for，循环取出绘制路径 trangram.p[i].x */</script></html>登入後複製
