教师投票系统（JSP+MySQL）
display.jsp
<%@ page language="java" import="java.sql.*" pageEncoding="gb2312"%>
<html>
<body>
<table align="center">
<caption>欢迎给老师投票</caption>
<tr bgcolor="yellow">
<td>编号</td>
<td>姓名</td>
<td>得票数</td>
<td>投票</td>
</tr>
<%
Class.forName("com.mysql.jdbc.Driver");
Connection conn=DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/school","root","laifu1990");
Statement stat=conn.createStatement();
String sql="select teacherno,teachername,vote from t_vote";
ResultSet rs=stat.executeQuery(sql);
while(rs.next())
{
String teacherno=rs.getString("teacherno");
String teachername=rs.getString("teachername");
int vote=rs.getInt("vote");
%>
<tr bgcolor="pink">
<td><%=teacherno %></td>
<td><%=teachername %></td>
<td><img src="img/bar.jpg" width="<%=vote %>>" height="10">
<%=vote%></td>
<td><a href="vote.jsp?teacherno=<%=teacherno%>">投票</a></td>
</tr>
<%
}
stat.close();
conn.close();
%>
</table>
</body>
</html>
vote.jsp
<%@ page language="java" import="java.sql.*" pageEncoding="gb2312"%>
<html>
<body>
<%
String teacherno = request.getParameter("teacherno");
Class.forName("com.mysql.jdbc.Driver");
Connection conn=DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/school","root","laifu1990");
String sql="update t_vote set vote=vote+1 where teacherno=?";
PreparedStatement ps=conn.prepareStatement(sql);
ps.setString(1, teacherno);
ps.executeUpdate();
ps.close();
conn.close();
%>
<jsp:forward page="display.jsp"></jsp:forward>
</body>
</html>
