关于c#:Mybatis配置数据库连接

首先resources下的mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE configuration        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-config.dtd"><!--外围配置文件--><configuration>    <environments default="development">        <environment id="development">            <transactionManager type="JDBC"/>            <dataSource type="POOLED">                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>                <property name="url" value="jdbc:mysql://localhost:3306/ssms?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>                <property name="username" value="root"/>                <property name="password" value="123456"/>            </dataSource>        </environment>    </environments>    <mappers>        <mapper resource="cn/zmxy/dao/UsersMapper.xml"/>    </mappers></configuration>

pojo实现类层的Java类(对应数据库表),比方Users表

public class Users {  private int id;  private String name;  private String pwd;  public Users(){}}

dao层的映射xml和Interface接口

UsersMapper.xml

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE mapper  PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"><!--namespace 命名空间 保定一个对应的dao/mapper接口--><mapper namespace="cn.zmxy.dao.UsersMapper"> <select id="getUserList" resultType="cn.zmxy.pojo.Users">  SELECT * FROM ssms.users    </select> <select id="getUserById" resultType="cn.zmxy.pojo.Users" parameterType="int">  SELECT * FROM ssms.users WHERE id = #{id}  </select> <insert id="addUser" parameterType="cn.zmxy.pojo.Users">  INSERT INTO ssms.users (id, name, pwd) VALUES (#{id}, #{name}, #{pwd})    </insert> <update id="updateUser" parameterType="cn.zmxy.pojo.Users">  UPDATE ssms.users SET name = #{name}, pwd = #{pwd} WHERE id = #{id}  </update> <delete id="deleteUser" parameterType="int">  DELETE FROM ssms.users WHERE id = #{id}  </delete></mapper>

UsersMapper.java

package cn.zmxy.dao;import cn.zmxy.pojo.Users;import java.util.List;public interface UsersMapper {  // 查问全副用户  public List<Users> getUserList();  // 依据ID查问用户  public Users getUserById(int id);  // 增加用户  public int addUser(Users user);  // 批改用户  public int updateUser(Users user);  // 删除用户  public int deleteUser(int id);}

写一个utils类，获取SqlSession

MyBatisUtils.java

package cn.zmxy.utils;import org.apache.ibatis.io.Resources;import org.apache.ibatis.session.SqlSession;import org.apache.ibatis.session.SqlSessionFactory;import org.apache.ibatis.session.SqlSessionFactoryBuilder;import java.io.IOException;import java.io.InputStream;public class MyBatisUtils {  private static SqlSessionFactory sqlSessionFactory;  static {  try {  String resource = "mybatis-config.xml";  InputStream is = Resources.getResourceAsStream(resource);  sqlSessionFactory = new SqlSessionFactoryBuilder().build(is); } catch (IOException e) {  e.printStackTrace(); } }  public static SqlSession getSqlSession() {  return sqlSessionFactory.openSession(); }}

最初就能够调用了，写一个test类

UserMapperTest.java

package cn.zmxy.dao;import cn.zmxy.pojo.Users;import cn.zmxy.utils.MyBatisUtils;import org.apache.ibatis.session.SqlSession;import org.junit.Test;import java.util.List;public class UserDaoTest {  @Test  public void test() {  // 第一步，获取SqlSession对象  SqlSession sqlSession = MyBatisUtils.getSqlSession();  // 第二步，执行SQL  UsersMapper usersMapper = sqlSession.getMapper(UsersMapper.class);  List<Users> userList = usersMapper.getUserList();  // 打印users  for (Users users : userList) {  System.out.println(users); }  // 敞开SqlSession  sqlSession.close(); }  @Test  public void getUserById() {  // 第一步，获取SqlSession对象  SqlSession sqlSession = MyBatisUtils.getSqlSession();  UsersMapper mapper = sqlSession.getMapper(UsersMapper.class);  Users user = mapper.getUserById(1);  System.out.println(user);  // 敞开SqlSession  sqlSession.close(); }  @Test  public void addUser() {  // 第一步，获取SqlSession对象  SqlSession sqlSession = MyBatisUtils.getSqlSession();  UsersMapper mapper = sqlSession.getMapper(UsersMapper.class);  int num = mapper.addUser(new Users(0, "露露", "1234"));  System.out.println("受影响行数：" + num);  sqlSession.commit();  // 敞开SqlSession  sqlSession.close(); }  @Test  public void updateUser() {  // 第一步，获取SqlSession对象  SqlSession sqlSession = MyBatisUtils.getSqlSession();  UsersMapper mapper = sqlSession.getMapper(UsersMapper.class);  int num = mapper.updateUser(new Users(3, "露露", "1234"));  System.out.println("受影响行数：" + num);  sqlSession.commit();  // 敞开SqlSession  sqlSession.close(); }  @Test  public void deleteUser() {  // 第一步，获取SqlSession对象  SqlSession sqlSession = MyBatisUtils.getSqlSession();  UsersMapper mapper = sqlSession.getMapper(UsersMapper.class);  int num = mapper.deleteUser(11);  System.out.println("受影响行数：" + num);  sqlSession.commit();  // 敞开SqlSession  sqlSession.close(); }}