JavaScript 绘制 sin 曲线代码如下 ：
<! doctype html> <html> <head> <스타일 유형 = "text/css"> #mycanvas {background-color : CornflowerBlue; }. var content = my_canvas.getContext ( "2d"); content.beginpath (); content.moveto (10, 100); for (var i = 1; i <200; i += 0.1) {var x = i * 10; var y = math.sin (i) * 10 + 100; content.lineto (x, y); } content.Stroke (); content.closepath (); } </script> </head> <body onload = "draw ()"> <canvas id = "mycanvas"> </canvas> </body> </html>动态效果 ：
<! doctype html> <html> <head> <스타일 유형 = "text/css"> #mycanvas {background-color : CornflowerBlue; } </style> <script type = "text/javaScript"> var i = 1; var x = 1; var y = 100; 함수 movesin () {var my_canvas = document.getElementById ( "mycanvas"); var content = my_canvas.getContext ( "2d"); content.beginpath (); content.moveto (x, y); I += 0.1; x = i * 10; y = math.sin (i) * 10 + 100; content.lineto (x, y); content.stroke (); content.closepath (); } setInterVal (movesin, 10); </script> </head> <body onload = "movesin ()"> <canvas id = "mycanvas"> </canvas> </body> </html>