求帮忙!!! <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>无标题文档</title> </head>
<body> <script language="javascript"> var seq=0; function type(){ var msg="I am very good"; var len=msg.length; var output; output=msg.substring(0,seq); document.write(output); if(seq<=len){ seq++; setTimeout("type()",500) } else { document.write("ok"); } } type(); </script>