这样表单为什么被提交?
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head>
<SCRIPT language=vbscript>
Function checkdata()
checkdata = Flase
End Function
</SCRIPT>
<body>
<form action="a.asp" method="post" name="form1" onSubmit="checkdata()">
<p>qwe
<input type="text" name="textfield">
</p>
<p>asd
<input type="text" name="textfield2">
<input type="submit" name="Submit" value="Submit">
</p>
</form>
</body>
</html>