建立条件首先一定要确定自己的mysql，tomcat,eclipse连接是正确的。
index.jsp很简单，就一个跳转。
<%
response.sendRedirect("lg.jsp");
%>
lg.jsp 实现登录框架
<%@ page contentType="text/html; charset=utf-8" %>
<html>
<head>
<title>
login
</title>
</head>
<center>
Prease input UserName and Pssword!!
</center>
<body bgcolor="#ffffff">
<%String flag=request.getParameter("flag");
if(flag!=null&&flag.equals("0")){
out.println("Pls input valid username and password!<br><br>");
}
%>
<form name="form1" method="post" action="login.jsp">
<center>
<input name="UserName" type="text" ><br/>
<input name="Password" type="password"><br/>
<input name="submit" type="submit" value="submit">
<input name="reset" type="reset" value="reset">
</center>
</form>
</body>
</html>
login.jsp 文件
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.sql.*"%>
<html>
<head>
<title>用户登陆</title>
</head>
<body>
<%
String UserName=request.getParameter("UserName");
String Password=request.getParameter("Password");
ResultSet rs=null;
Statement stmt=null;
Connection con=null;
boolean flag=false;
try{
//驱动程序名
String driverName="com.mysql.jdbc.Driver";
//数据库用户名
String userName="test";
//密码
String userPasswd="123456";
//数据库名
String dbName="along";
//表名
String tableName="user";
String url="jdbc:mysql://localhost/"+dbName+"?user="+userName+"&password="+userPasswd;
Class.forName("com.mysql.jdbc.Driver").newInstance();
con=DriverManager.getConnection(url);
stmt = con.createStatement();
String sql="select * from user where UserName='"+UserName+"' and Password='"+Password+"'";
System.out.println("login: "+sql);
rs = stmt.executeQuery(sql);
//System.out.printl
有两种传参方式
一、get方式：
这种方式将参数写在url中，举例来说，如果目标传参页面是target.jsp,那么在url里可以这么写：
http://..../target.jsp? <Param1> = <value1> & <Param2> = <value2> &...
&n ......
<%@ page contentType="text/html; charset=gbk" language="java" import="java.io.*" buffer="64kb" %>
<%
String path_in = "";
String content = "";
path_in = request.getRealPath("/")+"admin"+File.separator+ ......
