[VB] รบกวนช่วยดูเออเร่อด้วยค่ะ โค้ด login + กำหนดสิทธิ์ให้ล็อคอินได้เฉพาะบางกลุ่ม

Imports System.Data
Imports System.Data.OleDb
Public Class LoginForm
    Dim StrConn As String
    Dim Conn As New OleDbConnection
    Dim da As OleDbDataAdapter
    Dim ds As New DataSet

    Dim dt As DataTable
    Dim dr As DataRow


    Dim CurrentEmployees As Integer
    Dim IsFind As Boolean = False
    Dim btnChk As String

    Dim Cnn As New OleDbConnection(Cnnstring)
    Dim Cnnstring As String
    Dim SqlSelect As String
    Dim OleReader As OleDbDataReader
    Dim UserIDA As String
    Dim PassIDA As String


    Private Sub LoginForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        StrConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\ae\LibralyProject\libraly.accdb"

        With Conn
            If .State = ConnectionState.Open Then Close()
            .ConnectionString = StrConn
            .Open()

        End With
    End Sub
    Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OK.Click

        Cnnstring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\ae\LibralyProject\libraly.accdb"
        With Cnn
            If .State = ConnectionState.Open Then Close()
            .ConnectionString = Cnnstring
            .Open()
            .Close()
        End With
        If txtUserName.Text = "" Or txtPwd.Text = "" Then
            MessageBox.Show("ใส่ข้อมูล", "No UserID", MessageBoxButtons.OK, MessageBoxIcon.Error)
        Else
            ReadMyData(Cnnstring)
        End If
    End Sub
    Public Sub ReadMyData(ByVal myConnString As String)
        Dim str_idname As String = ""
        Dim str_password As String = ""
        On Error GoTo 0
        With Cnn
            If .State = ConnectionState.Open Then Close()
            .ConnectionString = Cnnstring
            .Open()
        End With
        SqlSelect = "select * from users Where userid = '" & txtUserName.Text & "' and userpassword = '" & txtPwd.Text & "'"
        Dim OleCommand As New OleDbCommand(SqlSelect, Cnn)
        OleReader = OleCommand.ExecuteReader
        OleReader.Read()
        If Not OleReader.HasRows Then
            str_idname = OleReader.Item("userid")
            str_password = OleReader.Item("userpassword")
        Else
            MessageBox.Show("User name or password Incorrec")
        End If

        Cnn.Close()
        If txtUserName.Text = str_idname And txtPwd.Text = str_password Then
            Form2.Show()
            txtUserName.Text = ""
            txtPwd.Text = ""
            Me.Hide()
        Else
            MessageBox.Show("กรุณาใส่ข้อมูลให้ถูกต้อง", Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Warning)

        End If
    End Sub
    Private Sub Cancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Cancel.Click
        Me.Close()
    End Sub



End Class