如何连接到 MySQL 数据库？

You can use Package Manager to add it as a package and it is the easiest way. You don't need anything else to work with a MySQL database.

Or you can run this command in Package Manager Console:

PM> Install-Package MySql.Data

NuGet MySql.Data

Install Oracle's MySql.Data NuGet package.

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


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


public string Server { get; set; }
public string DatabaseName { get; set; }
public string UserName { get; set; }
public string Password { get; set; }


private MySqlConnection Connection { get; set;}


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={0}; database={1}; UID={2}; password={3}", Server, DatabaseName, UserName, Password);
Connection = new MySqlConnection(connstring);
Connection.Open();
}
    

return true;
}
    

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

Example:

var dbCon = DBConnection.Instance();
dbCon.Server = "YourServer";
dbCon.DatabaseName = "YourDatabase";
dbCon.UserName = "YourUsername";
dbCon.Password = "YourPassword";
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();
}

Looking at the code below, I tried it and found: Instead of writing DBCon = DBConnection.Instance(); you should put DBConnection DBCon - new DBConnection(); (That worked for me)

and instead of MySqlComman cmd = new MySqlComman(query, DBCon.GetConnection()); you should put MySqlCommand cmd = new MySqlCommand(query, DBCon.GetConnection()); (it's missing the d)

 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);
}

You must to download MySQLConnection NET from here.

Then you need add MySql.Data.DLL to MSVisualStudio like this:

1. Open menu project
2. Add
3. Reference
4. Browse to C:\Program Files (x86)\MySQL\MySQL Connector Net 8.0.12\Assemblies\v4.5.2
5. Add MySql.Data.dll

If you want to know more visit: enter link description here

To use in the code you must import the library:

using MySql.Data.MySqlClient;

An example with connectio to Mysql database (NO SSL MODE) by means of Click event:

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();
}
}


}

Another library to consider is MySqlConnector, https://mysqlconnector.net/. Mysql.Data is under a GPL license, whereas MySqlConnector is MIT.