login
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP </title>
</head>
<body>
<form action="/day1030jsp/02.jsp" method="post" >
用戶名:<input type="text" name="username"/><br/>
密碼:<input type="password" name="password"/><br/>
<input type="submit" value="登錄"/>
</form>
</body>
</html>
Dologin
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%
//獲取前端數據
String username=request.getParameter("username");
String password=request.getParameter("password");
//2.處理業務邏輯 登陸
if("admin".equals(username)&&"123456".equals(password)){
//分發轉向
request.getRequestDispatcher("/success.jsp").forward(request, response);
}else{
//失敗
response.sendRedirect(request.getContextPath()+"/01.jsp");
}
%>
success.jsp
<body>
登陸成功
<%
String username=request.getParameter("username");
out.write(username);
%>
</body>
更改後
login
<body>
<%
String msg=(String)request.getAttribute("msg");
if(msg!=null){
out.print(msg);
}
%>
<form action="/day1030jsp/servlet/login" method="post" >
用戶名:<input type="text" name="username"/><br/>
密碼:<input type="password" name="password"/><br/>
<input type="submit" value="登錄"/>
</form>
</body>
dologin
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//編碼
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
//獲取前端數據
String username=request.getParameter("username");
String password=request.getParameter("password");
//2.處理業務邏輯 登陸
if("admin".equals(username)&&"123456".equals(password)){
//分發轉向
//請求轉發 攜帶數據
//request.getRequestDispatcher("/success.jsp").forward(request, response);
//response.sendRedirect(location) 重定向 路徑 location
request.getSession().setAttribute("username",username); //通過session存入數據
response.sendRedirect(request.getContextPath()+"/success.jsp");
}else{
//失敗
//response.sendRedirect(request.getContextPath()+"/01.jsp");
request.setAttribute("msg", "服務器繁忙稍後再試");
request.getRequestDispatcher("/01.jsp").forward(request,response);
}
}
success.jsp
<body>
登陸成功
<%
/* String username=request.getParameter("username");
out.write(username); */
String username=(String)request.getSession().getAttribute("username");
out.write(username);
%>
</body>