เกี่ยวกับการดึงข้อมูลจากคลาสคร๊าบบบ ของโปรแกรม VB.net กับ SQL Server 2014

Option Explicit On
Option Strict On
Imports System.Data
Imports System.Data.SqlClient
Imports MySql.Data.MySqlClient

Friend Class connectionDB

Public  connectionSQL As MySqlConnection
Public commandSQL As MySqlCommand
Public readerSQL As MySqlDataAdapter

Public Sub connectMySQL()
Try
connectionSQL = New MySqlConnection
connectionSQL.ConnectionString = "Data Source=localhost;Initial Catalog=Inventory;User ID=sa;Password=30082531"
If connectionSQL.State = ConnectionState.Closed Then
connectionSQL.Open()
End If

Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub

Public Sub closeSQL()
Try
connectionSQL.Close()
commandSQL.Cancel()
connectionSQL = Nothing
commandSQL = Nothing
readerSQL = Nothing
Catch ex As Exception

End Try

End Sub

End Class

Option Explicit On
Option Strict On
Imports System.Data
Imports System.Data.SqlClient
Imports MySql.Data.MySqlClient

Public Class Form1



Private Sub frmLogin_Load(sender As Object, e As EventArgs) Handles MyBase.Load
connectionDB.connectMySQL() 'ไม่จำเป็นต้องประกาศตัวแปร

End Sub
End Class