将 MySQL 数据库连接到 Visual Studio

Connecting MySQL database with Visual Studio

我使用以下代码从服务器资源管理器创建了一个 MySQL 服务器数据库文件来连接 MySQL 数据库:

private void DataAdd_Load(object sender, EventArgs e)
{
    try
    {
        var conn = new MySqlConnection();
        conn.ConnectionString =
             "Data Source=(LocalDB)\MSSQLLocalDB;" +
             "User Instance=true;" +
             "Integrated Security=false;" +
             "AttachDbFilename=C:\Path\filename.MDF;";
          conn.Open();

        MessageBox.Show("Connected to database");
    }
    catch (Exception e1)
    {
        MessageBox.Show("Connection failed");
    }
}

但是连接总是失败。

调试时发现的错误:

Exception thrown: 'System.Data.SqlClient.SqlException' in System.Data.dll ("The user instance login flag is not allowed when connecting to a user instance of SQL Server. The connection will be closed.")

您将需要使用 MySQL连接,如此处所回答:

ASP.NET use SqlConnection connect MySQL

MySQL 连接库可能未包含在您的解决方案中,因此您需要下载它。并将 var conn = new SqlConnection(); 更改为:

var conn = new MySqlConnection();

要连接到 MySQL,您需要 MySqlConnection 和正确的 MySQL 连接字符串:

private void DataAdd_Load(object sender, EventArgs e)
{
    try
    {
        var conn = new MySqlConnection(@"Server=192.168.1.10;Database=myDB;Uid=myUsername;Pwd=myPassword;");
        conn.Open();
        MessageBox.Show("Connected to database");
    }
    catch (Exception e1)
    {
        MessageBox.Show("Connection failed");
    }
}