JSP教程-在JSP中创建CRUD示例
我们可以在JSP中轻松创建CRUD（创建、读取、更新、删除）示例。这里，我们使用DAO文件来处理数据库操作和JSTL来遍历记录。
CRUD示例
Eclipse中的目录结构
主要页面和代码
index.jsp
主页面，提供添加用户和查看用户的链接。
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>JSP CRUD Example</title>
</head>
<body>
<h1>JSP CRUD Example</h1>
<a href="adduserform.jsp">Add User</a>
<a href="viewusers.jsp">View Users</a>
</body>
</html>adduserform.jsp
添加用户的表单页面，嵌入了用户表单。
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Add User Form</title>
</head>
<body>
<jsp:include page="userform.html"></jsp:include>
</body>
</html>userform.html
用户数据的具体输入表单。
<a href="viewusers.jsp">View All Records</a><br/>
<h1>Add New User</h1>
<form action="adduser.jsp" method="post">
<table>
<tr><td>Name:</td><td><input type="text" name="name"/></td></tr>
<tr><td>Password:</td><td><input type="password" name="password"/></td></tr>
<tr><td>Email:</td><td><input type="email" name="email"/></td></tr>
<tr><td>Sex:</td><td><input type="radio" name="sex" value="male"/>Male
<input type="radio" name="sex" value="female"/>Female</td></tr>
<tr><td>Country:</td><td><select name="country" style="width:155px">
<option>India</option><option>Pakistan</option><option>Afghanistan</option>
<option>Berma</option><option>Other</option></select></td></tr>
<tr><td colspan="2"><input type="submit" value="Add User"/></td></tr>
</table>
</form>UserDao.java
负责数据库操作的DAO类，包括增加、删除、更新和获取用户。
package cn.javatiku.dao;
import cn.javatiku.bean.User;
import java.sql.*;
public class UserDao {
// 连接数据库
public static Connection getConnection(){
Connection con = null;
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "", "");
} catch(Exception e) { System.out.println(e); }
return con;
}
// 保存用户
public static int save(User u){
int status = 0;
try {
Connection con = getConnection();
PreparedStatement ps = con.prepareStatement("insert into register(name,password,email,sex,country) values(?,?,?,?,?)");
ps.setString(1, u.getName());
ps.setString(2, u.getPassword());
ps.setString(3, u.getEmail());
ps.setString(4, u.getSex());
ps.setString(5, u.getCountry());
status = ps.executeUpdate();
} catch(Exception e) { System.out.println(e); }
return status;
}
// 更新用户
public static int update(User u){
int status = 0;
try {
Connection con = getConnection();
PreparedStatement ps = con.prepareStatement("update register set name=?,password=?,email=?,sex=?,country=? where id=?");
ps.setString(1, u.getName());
ps.setString(2, u.getPassword());
ps.setString(3, u.getEmail());
ps.setString(4, u.getSex());
ps.setString(5, u.getCountry());
ps.setInt(6, u.getId());
status = ps.executeUpdate();
} catch(Exception e) { System.out.println(e); }
return status;
}
// 删除用户
public static int delete(User u){
int status = 0;
try {
Connection con = getConnection();
PreparedStatement ps = con.prepareStatement("delete from register where id=?");
ps.setInt(1, u.getId());
status = ps.executeUpdate();
} catch(Exception e) { System.out.println(e); }
return status;
}
// 获取所有用户记录
public static List<User> getAllRecords(){
List<User> list = new ArrayList<User>();
try {
Connection con = getConnection();
PreparedStatement ps = con.prepareStatement("select * from register");
ResultSet rs = ps.executeQuery();
while(rs.next()){
User u = new User();
u.setId(rs.getInt("id"));
u.setName(rs.getString("name"));
u.setPassword(rs.getString("password"));
u.setEmail(rs.getString("email"));
u.setSex(rs.getString("sex"));
u.setCountry(rs.getString("country"));
list.add(u);
}
} catch(Exception e) { System.out.println(e); }
return list;
}
// 根据ID获取单条记录
public static User getRecordById(int id){
User u = null;
try {
Connection con = getConnection();
PreparedStatement ps = con.prepareStatement("select * from register where id=?");
ps.setInt(1, id);
ResultSet rs = ps.executeQuery();
while(rs.next()){
u = new User();
u.setId(rs.getInt("id"));
u.setName(rs.getString("name"));
u.setPassword(rs.getString("password"));
u.setEmail(rs.getString("email"));
u.setSex(rs.getString("sex"));
u.setCountry(rs.getString("country"));
}
} catch(Exception e) { System.out.println(e); }
return u;
}
}结果
