Question

我是C＃编程的新手，但希望能够访问MySQL数据库（没有MS SQL的资金）

但是我有一个问题;我知道你需要有“MySQL连接器/ NET”和“用于Visual Studio的MySQL”来开发C＃应用程序，但安装应用程序的人是否也需要它们？（我可以用程序释放连接器DLL吗？）

由于

编辑：最终用户或连接器都需要它们吗？还有什么他们需要的吗？

Answer 1

using MySql.Data;
using MySql.Data.MySqlClient;

namespace Data
{
    public class DBConnection
    {
        private DBConnection()
        {
        }

        private string databaseName = string.Empty;
        public string DatabaseName
        {
            get { return databaseName; }
            set { databaseName = value; }
        }

        public string Password { get; set; }
        private MySqlConnection connection = null;
        public MySqlConnection Connection
        {
            get { return connection; }
        }

        private static DBConnection _instance = null;
        public static DBConnection Instance()
        {
            if (_instance == null)
                _instance = new DBConnection();
           return _instance;
        }

        public bool IsConnect()
        {
            if (Connection == null)
            {
                if (String.IsNullOrEmpty(databaseName))
                    return false;
                string connstring = string.Format("Server=localhost; database={0}; UID=UserName; password=your password", databaseName);
                connection = new MySqlConnection(connstring);
                connection.Open();
            }

            return true;
        }

        public void Close()
        {
            connection.Close();
        }        
    }
}

示例：

var dbCon = DBConnection.Instance();
dbCon.DatabaseName = "YourDatabase";
if (dbCon.IsConnect())
{
    //suppose col0 and col1 are defined as VARCHAR in the DB
    string query = "SELECT col0,col1 FROM YourTable";
    var cmd = new MySqlCommand(query, dbCon.Connection);
    var reader = cmd.ExecuteReader();
    while(reader.Read())
    {
        string someStringFromColumnZero = reader.GetString(0);
        string someStringFromColumnOne = reader.GetString(1);
        Console.WriteLine(someStringFromColumnZero + "," + someStringFromColumnOne);
    }
    dbCon.Close();
}

Answer 2

您可以使用程序包管理器将其添加为程序包，这是最简单的方法。你不需要任何其他东西来使用mysql数据库。

或者您可以在程序包管理器控制台中运行以下命令

PM> Install-Package MySql.Data

NUGET Mysql.Data

Answer 3

您必须从here下载MySQLConnection NET。

然后您需要像这样将MySql.Data.DLL添加到MSVisualStudio：

打开菜单项目
添加
参考
浏览到C:\Program Files (x86)\MySQL\MySQL Connector Net 8.0.12\Assemblies\v4.5.2
添加MySql.Data.dll

如果您想了解更多信息，请访问：enter link description here

要在代码中使用，必须导入库：

using MySql.Data.MySqlClient;

使用点击事件：

来连接到Mysql数据库（无SSL模式）的示例

using System;
using System.Windows;
using MySql.Data.MySqlClient;


namespace Deportes_WPF
{

public partial class Login : Window
{
    private MySqlConnection connection;
    private string server;
    private string database;
    private string user;
    private string password;
    private string port;
    private string connectionString;
    private string sslM;

    public Login()
    {
        InitializeComponent();

        server = "server_name";
        database = "database_name";
        user = "user_id";
        password = "password";
        port = "3306";
        sslM = "none";

        connectionString = String.Format("server={0};port={1};user id={2}; password={3}; database={4}; SslMode={5}", server, port, user, password, database, sslM);

        connection = new MySqlConnection(connectionString);
    }

    private void conexion()
    {
        try
        {
            connection.Open();

            MessageBox.Show("successful connection");

            connection.Close();
        }
        catch (MySqlException ex)
        {
            MessageBox.Show(ex.Message + connectionString);
        }
    }

    private void btn1_Click(object sender, RoutedEventArgs e)
    {
        conexion();
    }
  }

}

Answer 4

查看下面的代码，我试了一下，发现：不应该写DBCon = DBConnection.Instance();，而应该放DBConnection DBCon - new DBConnection();（这对我有用）

而不是MySqlComman cmd = new MySqlComman(query, DBCon.GetConnection());你应该放MySqlCommand cmd = new MySqlCommand(query, DBCon.GetConnection());（它缺少d）

Answer 5

要考虑的另一个库是MySqlConnector https://mysqlconnector.net/。 Mysql.Data受GPL许可，而MySqlConnector是MIT。

Answer 6

 private void Initialize()
    {
        server = "localhost";
        database = "connectcsharptomysql";
        uid = "username";
        password = "password";
        string connectionString;
        connectionString = "SERVER=" + server + ";" + "DATABASE=" + 
        database + ";" + "U`enter code here`ID=" + uid + ";" + "PASSWORD=" + password + ";";

        connection = new MySqlConnection(connectionString);
    }

如何连接MySQL数据库？

6 个答案: