阶段练习-实现用户登录
目录
login.jsp
1、登录页面的表单
<form action="dologin.jsp" method="post">
<p class="main">
<label>用户名: </label>
<input name="username" value="" />
<label>密码: </label>
<input type="password" name="password" value="">
</p>
<p class="space">
<input type="submit" value="登录" class="login" style="cursor: pointer;"/>
</p>
</form>
2、分析
①action为JSP处理业务逻辑，这里新建一个dologin.jsp来处理
②<input type="password">input文本框的类型type设置为text就是明文显示，type设置为password，再输入密码就是*号了
③cursor: pointer提交登录时设置小手
dologin.jsp
- 业务逻辑以及分析
<%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
String username ="";
String password ="";
request.setCharacterEncoding("utf-8");//防止中文乱码
username = request.getParameter("username");
password = request.getParameter("password");
//如果用户和密码都等于admin,则登录成功
if("admin".equals(username)&&"admin".equals(password))
{
session.setAttribute("loginUser", username);
request.getRequestDispatcher("login_success.jsp").forward(request, response);
}
else
{
response.sendRedirect("login_failure.jsp");
%>
login_success.jsp
1、在dologin.jsp中request.getRequestDispatcher("login_success.jsp").forward(request, response);
将成功页面请求转发到dologin.jsp页面，URL地址不变。
2、写一个if判断，执行，获取用户名，在业务逻辑（dologin.jsp）利用session设置获取用户名，session.setAttribute("loginUser", username);
用JSP表达式获取用toString（）显示字符串
<%
String loginUser = "";
if(session.getAttribute("loginUser")!=null)
{
loginUser = session.getAttribute("loginUser").toString();
}
%>
欢迎您<font color="red"><%=loginUser%></font>,登录成功！
login_failure.jsp
1、登录失败返回登录页面login.jsp
登录失败！请检查用户或者密码!<br>
<a href="login.jsp">返回登录</a>
完整页面代码:
<%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<html>
<head>
<!-- Page title -->
<title>imooc - Login</title>
<!-- End of Page title -->
<!-- Libraries -->
<link type="text/css" href="css/login.css" rel="stylesheet" />
<link type="text/css" href="css/smoothness/jquery-ui-1.7.2.custom.html" rel="stylesheet" />
<script type="text/javascript" src="js/jquery-1.3.2.min.js"></script>
<script type="text/javascript" src="js/easyTooltip.js"></script>
<script type="text/javascript" src="js/jquery-ui-1.7.2.custom.min.js"></script>
<!-- End of Libraries -->
</head>
<body>
<div id="container">
<div class="logo">
<a href="#"><img src="assets/logo.png" alt="" /></a>
</div>
<div id="box">
</div>
</div>
</body>
</html>