jsp+servlet實現的驗證登陸
阿新 • • 發佈：2018-11-12
可以將業務邏輯處理和檢視相分離，使用jsp介面表示檢視，使用servlet處理業務邏輯
login.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<%
String msg=(String)request.getAttribute("msg");
if(msg!=null){
out.print(msg);
}
%>
<form action="dologin" method="post">
username:<input type="text" name="username" /><br>
password:<input type="password" name="password" /><br>
<input type="submit" value="submit" />
</form>
</body>
</html>
success.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
登陸成功
<%
String username=request.getParameter("username");
out.print(username+"歡迎你");
%>
</body>
</html>
fail.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
登陸成功
<%
String username=request.getParameter("username");
out.print(username+"歡迎你");
%>
</body>
</html>
業務邏輯處理
com.zk.myservlet.dologin.java
public class dologin extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//獲取表單資料
String username=request.getParameter("username");
String password=request.getParameter("password");
//處理業務邏輯
if("Tom".equals(username)&&"123".equals(password))
{
//分發轉向
request.getSession().setAttribute("username", username);
request.getRequestDispatcher("/success.jsp").forward(request, response);
//response.sendRedirect(request.getContextPath()+"/success.jsp");//丟失 username引數值 ，一次請求
}
else
{
//分發轉向
//request.getRequestDispatcher("/fail.jsp").forward(request,response);
//response.sendRedirect(request.getContextPath()+"/fail.jsp");
request.setAttribute("msg", "使用者名稱密碼不正確");
request.getRequestDispatcher("/login.jsp").forward(request,response);
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request,response);
}
}