C#三层架构实现WinForm连接Mysql显示数据库数据实例 首先创建数据库丨 学号 姓名 班级 QQ 微信 丨5列三层架构，即包含 BLL，DAL，Model，DBHelper，Winform必须 Mysql 包using MySql.Data.MySqlClient;请依照下列文件规范命名首先配置WinForm下 App.config 文件（Mysql数据库连接为例）<?xml version="1.0" encoding="utf-8" ?> <configuration> <connectionStrings> <add name ="NiceHanMySql" connectionString="server=数据库地址;port=端口号;user=数据库用户名;password=密码; database=数据库名;"/> </connectionStrings> <startup> <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6.1" /> </startup> </configuration>BLL 下 NiceBLL.cs文件代码using DAL; using Models; using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace BLL { public class NiceBLL { NiceDAL tableDal = new NiceDAL(); public List<NiceModel> GetTableList() { return tableDal.GetTablelist(); } public String NiceFormText() { return "NiceHan Mysql TextDate"; } public String SystemonLock() { return "NiceHanWinForm"; } } }DAL 下 NiceDAL.cs文件代码using Models; using SqlDbHelper; using System; using System.Collections.Generic; using System.Data; using System.Linq; using System.Reflection.Emit; using System.Text; using System.Threading.Tasks; namespace DAL { public class NiceDAL { public List<NiceModel> GetTablelist() { string sqlStr = "select * from PZ "; DataTable sTable = NiceDB.GetDataTable(sqlStr, null); List<NiceModel> tableList = new List<NiceModel>(); foreach (DataRow dr in sTable.Rows) { NiceModel tb = new NiceModel(); tb.学号 = (dr["Num"].ToString()); tb.姓名 = (dr["Name"].ToString()); tb.班级 = (dr["Class"].ToString()); tb.QQ = (dr["QQ"].ToString()); tb.微信 = (dr["Wx"].ToString()); tableList.Add(tb); } return tableList; } } }Model 下 NiceModel.cs文件代码using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace Models { public class NiceModel { public string 姓名 { set; get; } public string 学号 { set; get; } public string 班级 { set; get; } public string QQ { set; get; } public string 微信 { set; get; } } }DBhelper 下 NiceDB.cs文件代码using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Configuration; using System.Data; using MySql.Data.MySqlClient; namespace SqlDbHelper { public static class NiceDB { private static readonly string connStr = ConfigurationManager.ConnectionStrings["NiceHanMySql"].ConnectionString; public static int ExecuteNoneQuery(string sqlStr, params System.Data.SqlClient.SqlParameter[] pms) { using (MySqlConnection conn = new MySqlConnection(connStr)) { using (MySqlCommand cmd = new MySqlCommand(sqlStr, conn)) { if (pms != null) { cmd.Parameters.AddRange(pms); } conn.Open(); return cmd.ExecuteNonQuery(); } } } public static object ExecuteScalar(string sqlStr, params MySqlParameter[] pms) { using (MySqlConnection conn = new MySqlConnection(connStr)) { using (MySqlCommand cmd = new MySqlCommand(sqlStr, conn)) { if (pms != null) { cmd.Parameters.AddRange(pms); } conn.Open(); return cmd.ExecuteScalar(); } } } public static MySqlDataReader ExecuteReader(string sqlStr, params MySqlParameter[] pms) { using (MySqlConnection conn = new MySqlConnection(connStr)) { using (MySqlCommand cmd = new MySqlCommand(sqlStr, conn)) { if (pms != null) { cmd.Parameters.AddRange(pms); } try { conn.Open(); return cmd.ExecuteReader(); } catch { conn.Close(); conn.Dispose(); throw; } } } } public static DataTable GetDataTable(string sqlStr, params MySqlParameter[] pms) { using (MySqlDataAdapter adapter = new MySqlDataAdapter(sqlStr, connStr)) { DataTable dt = new DataTable(); if (pms != null) { adapter.SelectCommand.Parameters.AddRange(pms); } adapter.Fill(dt); return dt; } } } }Winform 下 NiceHanForm.cs文件代码using BLL; using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace NiceHanForm { public partial class NiceHanForm : Form { public NiceHanForm() { InitializeComponent(); } private void Form2_Load(object sender, EventArgs e) { NiceBLL tb = new NiceBLL(); this.Text = tb.SystemonLock(); this.WinForm.Text = tb.NiceFormText(); this.dataGridView1.DataSource = tb.GetTableList(); } } }恭喜你完成 运行调试即可