使用数据库的登录验证系统
有三个页面:
================
login.html
================
<form action="login.jsp" method="post">
用户名:<input type="text" name="uname" /><br />
密码:<input type="password" name="psd" /><br />
<input type="submit" value="登录" />
<input type="reset" value="重写" />
</form>
================
login.jsp
================
<%@ page import="java.sql.*" %>
<%
String uname=request.getParameter("uname");
String psd=request.getParameter("psd");
if(uname==null||psd==null)
{
response.sendRedirect("login.html");
}
else
{
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
String url="jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ="+application.getRealPath("db1.mdb");
Connection conn=DriverManager.getConnection(url,"","");
Statement state=conn.createStatement();
String sql="select * from usertable where name='"+uname+"' and psd='"+psd+"'";
out.print(sql);
ResultSet rs=state.executeQuery(sql);
if(rs.next())
{
session.setAttribute("uname",uname);
response.sendRedirect("workpage.jsp");
}
else
{
out.print("用户名或密码错误!");
}
state.close();
conn.close();
}
catch(Exception e)
{
out.print(e);
}
}
%>
================
workpage.jsp
================
<%
String uname=(String)session.getAttribute("uname");
if(uname==null)
{
response.sendRedirect("login.html");
}
else
{
out.print("登录成功!欢迎您!");
}