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我写的咋执行不了呢？请大神帮看看！~

来源：2-2 绘制直线、多边形和七巧板

weberrookie

2015-02-02 14:25

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:0},{x:600,y:600},{x:600,y:200}],color:"#ef3d61"},

{p:[{x:600,y:200},{x:600,y:600},{x:400,y:400}],color:"#f9f5la"},

{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");

canvas.width = 800;

canvas.height = 800;

var context = canvas.getContext("2d");

for(var i=0;i<tangram.length;i++){

draw(tangram[i],context);

//alert('aaaa')

}

function draw(piece,cxt){

cxt.beginPath();

cxt.moveTo(piece.p[0].x,piece.p[0].y);

for(var i=1 ; i<piece.p.lenght ; i++ ){

cxt.lineTo( piece.p[i].x , piece.p[i].y );

cxt.closePath();

cxt.fillStyle=piece.color;

cxt.fill();//填充色

}

写回答关注

4回答

hookdown

2015-03-26 22:26:04

for(var i=1 ; i<piece.p.lenght ; i++ ){
cxt.lineTo( piece.p[i].x , piece.p[i].y );
cxt.closePath();
cxt.fillStyle=piece.color;
cxt.fill();//填充色
}
}
这里有问题
    for(var i=1;i<piece.p.length;i++)
           cxt.lineTo(piece.p[i].x,piece.p[i].y);//应该只有这一条语句包含在for循环中

完整代码如下:
<!DOCTYPE html>
<html>
<head>
    <title>index.html</title>

    <meta name="keywords" content="keyword1,keyword2,keyword3">
    <meta name="description" content="this is my page">
    <meta name="content-type" content="text/html; charset=UTF-8">

    

</head>

<body>
    <canvas id="canvas" style="border:1px solid #aaa;
   display:block;margin:50px auto;">当前浏览器不支持canvas
   </canvas>

<script type="text/javascript">
   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:0},{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');
       canvas.width=800;
       canvas.height=800;


       var context=canvas.getContext('2d');

   for(var i=0;i<tangram.length;i++)
       draw(tangram[i],context)

   }

   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();


       cxt.strokeStyle="black";
       cxt.lineWidth=3;
       cxt.stroke();
   }
</script>

</body>
</html>

0 1
Minya

2015-02-05 16:47:49

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:0},{x:600,y:600},{x:600,y:200}],color:"#ef3d61"},
{p:[{x:600,y:200},{x:600,y:600},{x:400,y:400}],color:"#f9f5la"},
{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');
canvas.width=800;
canvas.height=800;
var context=canvas.getContext('2d');
for ( var i=0 ; i<tangram.length; i++)
draw(tangram[i], context )
}
function draw(pice , cxt ){
cxt.beginPath()
cxt.moveTo(pice.p[0].x , pice.p[0].y);
for (var i=1; i<pice.p.length ; i++)
cxt.lineTo(pice.p[i].x,pice.p[i].y);
cxt.closePath();
cxt.fillStyle=pice.color;
cxt.fill();
}

0 0
Setli

2015-02-02 15:19:33

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();

     cxt.strokeStyle="black";
     cxt.lineWidth=3;
     cxt.stroke();
}

1 0

weberr...

就是这么写的啊，就是执行不了

2015-02-02 15:22:33

共 1 条回复 >
Setli

2015-02-02 15:17:02

<canvas id="convas" style="border:#000 solid 1px; display:block; margin:50px auto">该浏览器不支持canvas</canvas>
不知道你前面有没有写上这个

1 0

weberr...

写了啊~

2015-02-02 15:20:11

共 1 条回复 >

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