| 范文 | 
		     这里给大家分享的是一个学习canvas的时候做的画空心圆与实心圆的练习题,非常简单。     <canvas id=canvas width=500 height=500 style=background-color: yellow;></canvas>     代码如下:     var canvas=document.getelementbyid(canvas);     var cxt=canvas.getcontext(2d);     //画一个空心圆     cxt.beginpath();     cxt.arc(200,200,50,0,360,false);     cxt.linewidth=5;     cxt.strokestyle=green;     cxt.stroke();//画空心圆     cxt.closepath();     //画一个实心圆     cxt.beginpath();     cxt.arc(200,100,50,0,360,false);     cxt.fillstyle=red;//填充颜色,默认是黑色     cxt.fill();//画实心圆     cxt.closepath();     //空心和实心的组合     cxt.beginpath();     cxt.arc(300,300,50,0,360,false);     cxt.fillstyle=red;     cxt.fill();     cxt.strokestyle=green;     cxt.stroke();     cxt.closepath(); |