jsp内置对象2
四、session
应用session实现用户登录:
login.jsp
<body> <form action="index.jsp" name="form1" method="post"> 用户名:<input type="text" name="user" id="user" style="width: 120px"><br> 密码:<input type="password" name="pwd" id="pwd" style="width:120px;"><br> <input type="submit" name="submit" value="登录"> </form> </body> </html>
index.jsp
<body> <% String[][] users={{"zhangsan","123"},{"lisi","123"},{"wanger","123"}}; String user=request.getParameter("user"); String pwd=request.getParameter("pwd"); boolean flag=false; for(int i=0;i<users.length;i++) { if(users[i][0].equalsIgnoreCase(user)) { if(users[i][1].equalsIgnoreCase(pwd)) { flag=true; break; } } } if(flag) { session.setAttribute("username", user); response.sendRedirect("main.jsp"); } else { response.sendRedirect("login.jsp"); } %> </body>
main.jsp
<body> <% String name=(String)session.getAttribute("username"); %> 欢迎光临:<%=name %> <a href="exit.jsp">[退出]</a>
exit.jsp
<% session.invalidate(); response.sendRedirect("login.jsp"); %>
失败并不可怕