ช่วยหน่อยนะคร้าบ ผม เมื่อถูกล็อคแล้วให้ติดต่อเจ้าหน้าที่ ผมอยากทราบว่า เมื่อการล็อกอินที่ถูกล็อคไป

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

Imports System.IO


Public Class frmlogin
    Inherits System.Windows.Forms.Form

    Dim da As New SqlDataAdapter
    Dim ds As DataSet = New DataSet
    Dim Invalid As Integer = 0
    Dim conn As New SqlConnection
    Dim strcon As String = "Data Source=lolove-e8faf31f;Initial Catalog = CD Center;Integrated Security= True; user id = sa; password= '' "
    Dim tmpRowsAffected As Long = 0
    Dim xmlFilePath As String = "C:\\UserlogFile.xml"
    Dim IsFind As Boolean = False
    ' Dim strconn AS String = "Data Source=lolove-e8faf31f;Initial Catalog = CD Center;Integrated Security = True;user id = sa; password = ''"


    Public tmpUserName As String = ""
    Private Sub Ok_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Ok.Click
        Dim conn As SqlConnection = New SqlConnection
        conn.ConnectionString = strcon

        If (TxtUsername.Text = "") Or (TxtPassword.Text = "") Then
            MessageBox.Show("กรุณาป้อนข้อมูลให้ครบ !!!", "ผลการตรวจสอบ", _
            MessageBoxButtons.OK, MessageBoxIcon.Warning)
            TxtUsername.Focus()
            Exit Sub
        End If

        Dim sqlUser As String = ""
        sqlUser = "SELECT * From UserName"
        sqlUser &= " where (username ='" & TxtUsername.Text & "')"
        sqlUser &= " AND (password='" & TxtPassword.Text & " ')"
        sqlUser &= " AND (IsNormal='1')"
        With conn
            If .State = ConnectionState.Open Then .Close()
            ' .ConnectionString = StrConn
            .Open()
        End With
        If IsFind = True Then
            ds.Tables("UserName").Clear()
        End If

        da = New SqlDataAdapter(sqlUser, conn)
        da.Fill(ds, "UserName")
        If ds.Tables("UserName").Rows.Count <> 0 Then
            IsFind = True
            Invalid = 0

            Dim fmain As New frmmain
            fmain.Show()
            Me.Hide()

            tmpUserName = TxtUsername.Text
        Else
            IsFind = False
            WriteLogFile()

            If Invalid = 3 Then
                UpdateInvalidUser()
                If tmpRowsAffected <> 0 Then
                    MessageBox.Show("คุณป้อนรหัส Password ผิด ชื่อ UserName:" & _
                    TxtUsername.Text & "ไม่สามารถใช้งานได้ชั่วคราว กรุณาติดต่อผู้ดูแลระบบ !!! ", _
                    "ผลการตรวจสอบ", MessageBoxButtons.OK, MessageBoxIcon.Warning)

                    TxtUsername.Text = ""
                    TxtUsername.Focus()
                    TxtPassword.Text = ""
                    Invalid = 0
                    Exit Sub
                End If
            End If
            MessageBox.Show("ข้อมูลผู้ใช้งานไม่ถูกต้อง ไม่สามารถเข้าระบบได้ !!!", "ผลการตรวจสอบ", _
            MessageBoxButtons.OK, MessageBoxIcon.Information)
            TxtPassword.Text = ""
            TxtPassword.Focus()
            End If
    End Sub

    Private Sub WriteLogFile()

        Dim today As Date
        Dim dsxml As DataSet
        Try
            dsxml.ReadXml(xmlFilePath, XmlReadMode.Auto)
            Dim dr As DataRow
            dr = dsxml.Tables(0).NewRow
            dr("Username") = TxtUsername.Text
            dr("Password") = TxtPassword.Text
            dr("DataTimeToLogin") = today
            dsxml.Tables(0).Rows.Add(dr)
            dsxml.WriteXml(xmlFilePath, XmlWriteMode.IgnoreSchema)
        Catch
            Dim strFirstContent As String = ""
            strFirstContent = "<UserLog>" & vbCrLf
            strFirstContent &= "<Username>" & TxtUsername.Text & "</Username>" & vbCrLf
            strFirstContent &= "<Password>" & TxtPassword.Text & "</Password>" & vbCrLf
            strFirstContent &= "<Datetimelogin>" & today & "</Datetimelogin>" & vbCrLf
            strFirstContent &= "</UserLog>"
            Dim sw As StreamWriter = New StreamWriter(xmlFilePath)
            sw.Write(strFirstContent)
            sw.Flush()
            sw.Close()
        End Try
        Invalid = Invalid + 1
    End Sub

    Private Sub UpdateInvalidUser()
        Dim conn As SqlConnection = New SqlConnection
        Dim SqlUpdate As String = ""
        SqlUpdate = "Update Username"
        SqlUpdate &= " set IsNormal = '0'"
        SqlUpdate &= "where (username=' " & TxtUsername.Text & " ')"

        With conn
            If .State = ConnectionState.Open Then .Close()
            .ConnectionString = strcon
            .Open()
        End With
        Dim tr As SqlTransaction
        Dim comUpdate As SqlCommand
        tr = conn.BeginTransaction
        comUpdate = New SqlCommand
        With comUpdate
            .CommandType = CommandType.Text
            .CommandText = SqlUpdate
            .Connection = conn
            .Transaction = tr
            tmpRowsAffected = .ExecuteNonQuery
        End With
        Invalid = 0
        tr.Commit()
    End Sub

    Private Sub FrmLogin_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim conn As SqlConnection = New SqlConnection
        Dim strconn As String = "Data Source=lolove-e8faf31f;Initial catalog=CD Center;Integrated Security = True"
        Cursor.Current = Cursors.WaitCursor

        With conn
            If .State = ConnectionState.Open Then .Close()
            .ConnectionString = strcon
            .Open()
        End With
        Cursor.Current = Cursors.Default
    End Sub
    Private Sub Ext_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Ext.Click
        If MessageBox.Show("คุณต้องการจบการทำงานใช่หรือไม่", "คำยืนยัน", MessageBoxButtons.YesNo, MessageBoxIcon.Question) = Windows.Forms.DialogResult.Yes Then
            End
        End If
    End Sub

End Class

If Invalid = 3 Then
UpdateInvalidUser()
If tmpRowsAffected <> 0 Then
MessageBox.Show("คุณป้อนรหัส Password ผิด ชื่อ UserName:" & _
TxtUsername.Text & "ไม่สามารถใช้งานได้ชั่วคราว กรุณาติดต่อผู้ดูแลระบบ !!! ", _
"ผลการตรวจสอบ", MessageBoxButtons.OK, MessageBoxIcon.Warning)

TxtUsername.Text = ""
TxtUsername.Focus()
TxtPassword.Text = ""
Invalid = 0