c# 连接Mysql数据库方法
一:通过MySql.Data实现连接Mysql数据库
目前该方法不需要本地安装运行环境;
1.1 Mysql数据库配置信息;
数据库名:TEST 数据库用户名:test 数据库地址:b.lifeiai.com 端口:3306 密码:123456
该数据库未安装在本地,使用宝塔面板驱动,所以需要设置数据库访问权限为所有人;
1.2 C# 引入mysql.data库
1.3 使用语句连接Mysql数据库
using System.Data; private void Form1_Load(object sender, EventArgs e) { String str = "server=b.lifeiai.com;port=3306;user=test ;password=123456;database=TEST;"; MySqlConnection conn = new MySqlConnection(str); conn.Open(); if (conn.State == ConnectionState.Open) { MessageBox.Show(" 连接成功!!!"); } else { MessageBox.Show("连接失败!!!"); } }
上述方法可判断是否能连接数据库,但是接下来我们进行增删改查的操作相应的会很麻烦,建议使用公共数据库处理方法MysqlConnect去解决;
1.4 拓展MysqlConnect助手类
using MySql.Data.MySqlClient; using System; using System.Data; using MySql.Data; namespace WenXinYiYanTest { public class MysqlConnect { private MySqlConnection conn = null; private MySqlCommand cmd = null; private MySqlDataReader sdr; private MySqlDataAdapter sda = null; public MysqlConnect() { string connStr = "server=b.lifeiai.com;port=3306;user=test ;password=123456;database=TEST;"; //获取MySql数据库连接字符串 conn = new MySqlConnection(connStr); //数据库连接 } /// <summary> /// 打开数据库链接 /// </summary> /// <returns></returns> private MySqlConnection GetConn() { if (conn.State == ConnectionState.Closed) { conn.Open(); } return conn; } /// <summary> /// 关闭数据库链接 /// </summary> private void GetConnClose() { if (conn.State == ConnectionState.Open) { conn.Close(); } } /// <summary> /// 执行不带参数的增删改SQL语句或存储过程 /// </summary> /// <param name="cmdText">增删改SQL语句或存储过程的字符串</param> /// <param name="ct">命令类型</param> /// <returns>受影响的函数</returns> public int ExecuteNonQuery(string cmdText, CommandType ct) { int res; using (cmd = new MySqlCommand(cmdText, GetConn())) { cmd.CommandType = ct; res = cmd.ExecuteNonQuery(); } return res; } /// <summary> /// 执行带参数的增删改SQL语句或存储过程 /// </summary> /// <param name="cmdText">增删改SQL语句或存储过程的字符串</param> /// <param name="paras">往存储过程或SQL中赋的参数集合</param> /// <param name="ct">命令类型</param> /// <returns>受影响的函数</returns> public int ExecuteNonQuery(string cmdText, MySqlParameter[] paras, CommandType ct) { int res; using (cmd = new MySqlCommand(cmdText, GetConn())) { cmd.CommandType = ct; cmd.Parameters.AddRange(paras); res = cmd.ExecuteNonQuery(); } return res; } /// <summary> /// 执行不带参数的查询SQL语句或存储过程 /// </summary> /// <param name="cmdText">查询SQL语句或存储过程的字符串</param> /// <param name="ct">命令类型</param> /// <returns>查询到的DataTable对象</returns> public DataTable ExecuteQuery(string cmdText, CommandType ct) { DataTable dt = new DataTable(); cmd = new MySqlCommand(cmdText, GetConn()); cmd.CommandType = ct; using (sdr = cmd.ExecuteReader(CommandBehavior.CloseConnection)) { dt.Load(sdr); } return dt; } /// <summary> /// 执行带参数的查询SQL语句或存储过程 /// </summary> /// <param name="cmdText">查询SQL语句或存储过程的字符串</param> /// <param name="paras">参数集合</param> /// <param name="ct">命令类型</param> /// <returns></returns> public DataTable ExecuteQuery(string cmdText, MySqlParameter[] paras, CommandType ct) { DataTable dt = new DataTable(); cmd = new MySqlCommand(cmdText, GetConn()); cmd.CommandType = ct; cmd.Parameters.AddRange(paras); using (sdr = cmd.ExecuteReader(CommandBehavior.CloseConnection)) { dt.Load(sdr); } return dt; } /// <summary> /// 执行指定数据库连接字符串的命令,返回DataSet. /// </summary> /// <param name="strSql">一个有效的数据库连接字符串</param> /// <returns>返回一个包含结果集的DataSet</returns> public DataSet ExecuteDataset(string strSql) { DataSet ds = new DataSet(); sda = new MySqlDataAdapter(strSql, GetConn()); try { sda.Fill(ds); } catch (Exception ex) { throw ex; } finally { GetConnClose(); } return ds; } } }
上述帮助类的文件:MysqlConnect.zip
1.5 MysqlConnect助手类使用方法(查、更)
using MySql.Data.MySqlClient; using Newtonsoft.Json; using System; using System.Data; using System.Windows.Forms; namespace WenXinYiYanTest { public partial class Form1 : Form { public Form1() { InitializeComponent(); } MysqlConnect mysqlConnect = new MysqlConnect(); private void Form1_Load(object sender, EventArgs e) { var sql = "UPDATE nual SET 字段 ='"+ 值变量+ "' WHERE 1"; //增、删、改无参处理方法,返回影响行数 var StateType = mysqlConnect.ExecuteNonQuery(sql, CommandType.Text); sql = "select * from nual WHERE 1"; //查询方法 sql = "select * from NUAL WHERE 1"; //无参查询数据,返回DataTable DataTable dt = mysqlConnect.ExecuteQuery(sql, CommandType.Text); dataGridView1.DataSource = dt; } } }