为什么得到的是null呢?
源文件如下
///// 1.html
<html>
<body>
<form method=post action="2.jsp">
what's your name?<input type=text name=usename size=20>
<p><input type=submit >
</form>
</body>
</html>
////////////////////2.jsp
<%
String name=request.getParameter("username");
session.setAttribute("thename",name);
%>
<html>
<body>
<a href="3.jsp">continue</a>
</body>
</html>
///////////////////////3.jsp
<html>
<body>
hello,<%=session.getAttribute("thename")%>
</body>
</html>