Imports MySql.Data.MySqlClient
'Comentando varias linhas Ctrl + K + C
'Descomentando varias linhas Ctrl + K + U
Public Class DBConnection
    Dim Conexao As MySqlConnection
    Dim cmd As MySqlCommand = New MySqlCommand()
    Public Sub New()
        Conexao = New MySqlConnection()
    End Sub

    Public Sub OpenConnection()
        Dim strConnString As String = "server=localhost;userid=root;password=;database=Vendas"

        If Conexao Is Nothing Or Conexao.State = ConnectionState.Broken Or Conexao.State = ConnectionState.Closed Then
            Conexao = New MySqlConnection()
            Conexao.ConnectionString = strConnString
            Conexao.Open()
        End If

    End Sub

    Public Sub CloseConnection()
        If Conexao.State = ConnectionState.Open Then
            Conexao.Close()
            Conexao.Dispose()
            Conexao = Nothing
        End If
    End Sub

    Public Function ExecuteDS(ByVal sql As String, ByRef tabela As String) As DataSet
        Dim ds As New DataSet
        Dim da As MySqlDataAdapter = New MySqlDataAdapter()

        Try
            OpenConnection()
            cmd.CommandType = CommandType.Text
            cmd.CommandText = sql
            cmd.Connection = Conexao
            da.SelectCommand = cmd
            da.Fill(ds, tabela)
            da.Dispose()
            Return ds
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
        Return ds
    End Function

End Class

Private Sub incluirRegistro(ByVal dr As DataRow)
        Dim reg As Integer
        Dim Conexao As MySqlConnection
        Dim comando As MySqlCommand
        Try
            Conexao = New MySqlConnection("server=localhost;uid=root;pwd=;database=vendas")
            Conexao.Open()
            comando = New MySqlCommand("INSERT INTO Clientes (Nome,Endereco,Email)VALUES ('" & Nome.Text & "','" & Endereco.Text & "','" & Email.Text & "')", Conexao)   '<<--here i need to use the variable of the class DBConection
            reg = comando.ExecuteNonQuery()

            MessageBox.Show(reg.ToString + " registro de Usuário incluido com sucesso.")
        Catch ex As MySqlException
            MessageBox.Show("Erro ao efetuar a conexão com a base de dados : " + ex.Message)
        Finally
            '   Conexao.Close()
        End Try
end sub