<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<canvas id="canvas" style=" width:800px; height:800px;margin:0px auto; display:block;">
/*判断浏览器 不兼容则切换浏览器*/
</canvas>
<script type="text/javascript">
/*七巧板*/
var tangram=[
{p:[{x:0,y:0},{x:800,y:0},{x:400,y:400}],color:"#caff67"},
{p:[{x:0,y:0},{x:400,y:400},{x:0,y:800}],color:"#67becf"},
{p:[{x:800,y:0},{x:800,y:400},{x:600,y:600},{x:600,y:200}],color:"#ef3d61"},
{p:[{x:600,y:200},{x:600,y:600},{x:400,y:400}],color:"f9f51a"},
{p:[{x:400,y:400},{x:600,y:600},{x:400,y:800},{x:200,y:600}],color:"#a594c0"},
{p:[{x:200,y:600},{x:400,y:800},{x:0,y:800}],color:"#fa8ecc"},
{p:[{x:800,y:400},{x:800,y:800},{x:400,y:800}],color:"#f6ca29"}
]
window.onload= function () {
var canvas=document.getElementById("canvas");//获取id
var cantext=canvas.getContext("2d");//2d图形
/*或者用if语句判断浏览器*/
if(canvas.getContext("2d")){
var cantext=canvas.getContext("2d");//2d图形
}else{
alert("此浏览器不支持canvas,请更换浏览器")
}
/*获取数组中的每一块*/
for(var i=0;i<tangram.length;i++){
draw(tangram[i],cantext)
};
/*获取每一块的每一个坐标*/
function draw(piece,cxt){
cxt.beginPath();
cxt.moveTo(piece.p[0].x,piece.p[0].y);//起点
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();
}
}
</script>
</body>
</html>function draw(piece,cxt){
cxt.beginPath();
cxt.moveTo(piece.p[0].x,piece.p[0].y);//起点
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();
}
这段代码不对 你自己看老师的 老师循环没{}。
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();
}
<canvas width="800px" height="800px"></canvas>
已解决 没有在js中设置宽高
canvas.width=800;
canvas.height=800;
但我在html中设置了宽高没有起作用，求解？？？？？？？？？？？
<canvas id="canvas" style=" width:800px; height:800px;margin:0px auto; display:block;">