C# WinApp ผมอยากหารูปแบบการแปลง string ให้เป็น datetime ครับ

    Public Shared Function StringToDate(ByVal strDate As String, ByVal Date_Format As String, Optional ByVal Era_Type As String = "en-US") As Date
        Dim dRet As Date
        Return If(Date.TryParseExact(strDate, Date_Format, New CultureInfo(Era_Type), DateTimeStyles.None, dRet), dRet, Nothing)
    End Function

Dim str2Date1 = StringToDate("31/12/2015", "dd/MM/yyyy", "en-US") --> 12/31/2015
Dim str2Date2 = StringToDate("31/12/2558", "dd/MM/yyyy", "th-TH") --> 12/31/2015

Me.Text = str2Date1 
'(คุณพยายามที่จะทำให้ String = Date โดยขาดเหตุผลกำกับ)
'--- ถ้ามันถูกต้องคุณคงไม่มีรูปภาพ Com1, Com2 มาประกอบ

Me.Text = str2Date1.ToString("dd/MM/yyyy", New CultureInfo("th-TH")) 'ต้องการ พ.ศ.
Me.Text = str2Date1.ToString("dd/MM/yyyy", New CultureInfo("en-GB")) 'ต้องการ ค.ศ. (อังกฤษ)
Me.Text = str2Date1.ToString("MM/dd/yyyy", New CultureInfo("en-US")) 'ต้องการ ค.ศ. (อังกฤษ-US)

Me.Text = str2Date1 

this.Text = str2Date1

Dim dtFixed As Date = New Date(2016, 1, 1) 'yyyy/MM/dd

Public Class Form1

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim str2Date1 = StringToDate("2559/12/31 08:30:20 AM +7", "dd/MM/yyyy", "th-TH")
        Dim dateNow As Date = Date.Parse(str2Date1)
        Me.Text = "The date and time are  UTC =>" & TimeZoneInfo.ConvertTimeToUtc(dateNow)
    End Sub
    Public Shared Function StringToDate(ByVal strDate As String, ByVal Date_Format As String, Optional ByVal Era_Type As String = "en-US") As Date
        Dim dRet As Date
        Return If(Date.TryParseExact(strDate, Date_Format, New CultureInfo(Era_Type), DateTimeStyles.None, dRet), dRet, Nothing)
    End Function
End Class

ีupdate table set new_date = date( flddate), flddate = '0'
where flddate REGEXP '^(19|20)[0-9][09]/[0-9][09]/[0-9][09]'
and flddate<>'0'

ีupdate table set new_date = date( concat( flddate, '-01-01)), flddate = '0'
where flddate REGEXP '^(19|20)[0-9][0-9]'
and flddate<>'0'

ีupdate table set new_date = date( concat( (flddate-543), '-01-01)), flddate = '0'
where flddate REGEXP '^2[4-5][0-9][0-9]'
and flddate<>'0'

        Dim s As New System.Text.StringBuilder()
        s.Append(" 2016/12 4 นา 12/13 12.13 หำ 6 กิโล มี (Jan. 13, 2012) Feb. 12, 12 – น้อย ")
        s.Append(" January 15, 1999 July 15, 2923  June 2 2343 7/25/23 08/22/3323  มก.      33, 2333 ")
        Dim p01 As String = "(?:(\d{1,2})/(\d{1,2})/(\d{2,4}))"
        Dim p02 As String = "(?:(\s\d{1,2})\s+(jan(?:uary){0,1}\.{0,1}|feb(?:ruary){0,1}\.{0,1}|mar(?:ch){0,1}\.{0,1}|apr(?:il){0,1}\.{0,1}|may\.{0,1}|jun(?:e){0,1}\.{0,1}|jul(?:y){0,1}\.{0,1}|aug(?:ust){0,1}\.{0,1}|sep(?:tember){0,1}\.{0,1}|oct(?:ober){0,1}\.{0,1}|nov(?:ember){0,1}\.{0,1}|dec(?:ember){0,1}\.{0,1})\s+(\d{2,4}))"
        Dim p03 As String = "(?:(jan(?:uary){0,1}\.{0,1}|feb(?:ruary){0,1}\.{0,1}|mar(?:ch){0,1}\.{0,1}|apr(?:il){0,1}\.{0,1}|may\.{0,1}|jun(?:e){0,1}\.{0,1}|jul(?:y){0,1}\.{0,1}|aug(?:ust){0,1}\.{0,1}|sep(?:tember){0,1}\.{0,1}|oct(?:ober){0,1}\.{0,1}|nov(?:ember){0,1}\.{0,1}|dec(?:ember){0,1}\.{0,1})\s+([0-9]{1,2})[\s,]+(\d{2,4}))"
        Dim p04 As String = "(?:(มก(?:ราคม){0,1}\.{0,1}|กุม(?:ภาพันธ์){0,1}\.{0,1}|มี(?:นายน){0,1}\.{0,1}|เม(?:ษายน){0,1}\.{0,1}|พฤ(?:ษภาคม){0,1}\.{0,1}|มิ(?:ถุนายน){0,1}\.{0,1}|กรก(?:ฏาคม){0,1}\.{0,1}|สิง(?:หายน){0,1}\.{0,1}|กัน(?:ยายน){0,1}\.{0,1}|ตุ(?:ลาคม){0,1}\.{0,1}|พฤศ(?:จิกายน){0,1}\.{0,1}|ธัน(?:วาคม){0,1}\.{0,1})\s+([0-9]{1,2})[\s,]+(\d{2,4}))"
        Dim p05 As String = "(?:(\d{1,2})/(\d{2,4}))" 'เดือน/ปี
        Dim p06 As String = "(?:(\d{2,4})/(\d{1,2}))" 'ปี/เดือน
        Dim p07 As String = "(?:(\d{1,2})-(\d{2,4}))" 'เดือน-ปี
        Dim p08 As String = "(?:(\d{2,4})-(\d{1,2}))" 'ปี-เดือน
        '...
        '...
        '...
        'More...
        Dim mc As MatchCollection = Regex.Matches(s.ToString(), p01 + "|" + p02 + "|" + p03 + "|" + p04 + "|" + p05 + "|" + p06 + "|" + p07 + "|" + p08, RegexOptions.IgnoreCase Or RegexOptions.IgnorePatternWhitespace)

        Dim lstPattern = {New With {.Name = "Jan", .Value = "01"},
                          New With {.Name = "Jan.", .Value = "01"},
                          New With {.Name = "January", .Value = "01"},
                          New With {.Name = "ม.ค.", .Value = "01"},
                          New With {.Name = "มกราคม", .Value = "01"}
                         }

        Dim lstSeparator = New Char() {"-"c, "/"c, "."c}
        Dim strArray = "นา-หำ/มี.น้อย".Split(lstSeparator)

        Dim sPattern = lstPattern.ToList().FindAll(Function(x) x.Name = "MatchCollection Value").FirstOrDefault()

        MsgBox(mc.Count)

Dim p09 As String = "(?:(jan(?:uary){0,1})(\d{2,4}))"
'เดือนอื่นฯก็ดู p04 ประกอบ

Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Text
Imports System.Windows.Forms
Imports System.Reflection

<ToolboxBitmap(GetType(System.Windows.Forms.ComboBox)), ToolboxItem(True), ToolboxItemFilter("System.Windows.Forms"), Description("Displays an editable text box with a drop-down list of permitted values.")> _
Partial Public Class myComboBox
    Inherits System.Windows.Forms.ComboBox
    Public Sub New()
        InitializeComponent()
    End Sub

    Private Shared _modalMenuFilter As Type
    Private Shared ReadOnly Property modalMenuFilter() As Type
        Get
            If _modalMenuFilter Is Nothing Then
                _modalMenuFilter = Type.[GetType]("System.Windows.Forms.ToolStripManager+ModalMenuFilter")
            End If
            If _modalMenuFilter Is Nothing Then
                _modalMenuFilter = New List(Of Type)(GetType(ToolStripManager).Assembly.GetTypes()).Find(Function(type__1) type__1.FullName = "System.Windows.Forms.ToolStripManager+ModalMenuFilter")
            End If
            Return _modalMenuFilter
        End Get
    End Property

    Private Shared _suspendMenuMode As MethodInfo
    Private Shared ReadOnly Property suspendMenuMode() As MethodInfo
        Get
            If _suspendMenuMode Is Nothing Then
                Dim t As Type = modalMenuFilter
                If t IsNot Nothing Then
                    _suspendMenuMode = t.GetMethod("SuspendMenuMode", BindingFlags.[Static] Or BindingFlags.NonPublic Or BindingFlags.[Public])
                End If
            End If
            Return _suspendMenuMode
        End Get
    End Property

    Private Shared Sub SuspendMenuModeX()
        Dim suspendMenuMode__1 As MethodInfo = myComboBox.suspendMenuMode
        If suspendMenuMode__1 IsNot Nothing Then
            suspendMenuMode__1.Invoke(Nothing, Nothing)
        End If
    End Sub

    Private Shared _resumeMenuMode As MethodInfo
    Private Shared ReadOnly Property resumeMenuMode() As MethodInfo
        Get
            If _resumeMenuMode Is Nothing Then
                Dim t As Type = modalMenuFilter
                If t IsNot Nothing Then
                    _resumeMenuMode = t.GetMethod("ResumeMenuMode", BindingFlags.[Static] Or BindingFlags.NonPublic Or BindingFlags.[Public])
                End If
            End If
            Return _resumeMenuMode
        End Get
    End Property

    Private Shared Sub ResumeMenuModeX()
        Dim resumeMenuMode__1 As MethodInfo = myComboBox.resumeMenuMode
        If resumeMenuMode__1 IsNot Nothing Then
            resumeMenuMode__1.Invoke(Nothing, Nothing)
        End If
    End Sub

    Protected Overrides Sub OnDropDown(e As EventArgs)
        MyBase.OnDropDown(e)
        SuspendMenuModeX()
    End Sub

    Protected Overrides Sub OnDropDownClosed(e As EventArgs)
        ResumeMenuModeX()
        MyBase.OnDropDownClosed(e)
    End Sub
End Class

Imports System.Drawing
Imports System.Runtime.InteropServices
Imports System.Windows.Forms
Imports System.Security
Imports System.Security.Permissions

Friend NotInheritable Class NativeMethods
    Private Sub New()
    End Sub

    Private Shared HWND_TOPMOST As New HandleRef(Nothing, New IntPtr(-1))
    Friend Const WM_NCHITTEST As Integer = &H84,
                 WM_NCACTIVATE As Integer = &H86,
                 WS_EX_TRANSPARENT As Integer = &H20,
                 WS_EX_TOOLWINDOW As Integer = &H80,
                 WS_EX_LAYERED As Integer = &H80000,
                 WS_EX_NOACTIVATE As Integer = &H8000000,
                 HTTRANSPARENT As Integer = -1,
                 HTLEFT As Integer = 10, HTRIGHT As Integer = 11,
                 HTTOP As Integer = 12, HTTOPLEFT As Integer = 13,
                 HTTOPRIGHT As Integer = 14,
                 HTBOTTOM As Integer = 15,
                 HTBOTTOMLEFT As Integer = 16,
                 HTBOTTOMRIGHT As Integer = 17,
                 WM_PRINT As Integer = &H317,
                 WM_USER As Integer = &H400,
                 WM_REFLECT As Integer = WM_USER + &H1C00,
                 WM_COMMAND As Integer = &H111,
                 CBN_DROPDOWN As Integer = 7,
                 WM_GETMINMAXINFO As Integer = &H24

    <Flags> _
    Friend Enum AnimationFlags As Integer
        Roll = &H0
        ' Uses a roll animation.
        HorizontalPositive = &H1
        ' Animates the window from left to right. This flag can be used with roll or slide animation.
        HorizontalNegative = &H2
        ' Animates the window from right to left. This flag can be used with roll or slide animation.
        VerticalPositive = &H4
        ' Animates the window from top to bottom. This flag can be used with roll or slide animation.
        VerticalNegative = &H8
        ' Animates the window from bottom to top. This flag can be used with roll or slide animation.
        Center = &H10
        ' Makes the window appear to collapse inward if Hide is used or expand outward if the Hide is not used.
        Hide = &H10000
        ' Hides the window. By default, the window is shown.
        Activate = &H20000
        ' Activates the window.
        Slide = &H40000
        ' Uses a slide animation. By default, roll animation is used.
        Blend = &H80000
        ' Uses a fade effect. This flag can be used only with a top-level window.
        Mask = &HFFFFF
    End Enum

    <SuppressUnmanagedCodeSecurity> _
    <DllImport("user32.dll", CharSet:=CharSet.Auto)> _
    Private Shared Function AnimateWindow(windowHandle As HandleRef, time As Integer, flags As AnimationFlags) As Integer
    End Function

    Friend Shared Sub AnimateWindow(control As Control, time As Integer, flags As AnimationFlags)
        Try
            Dim sp As New SecurityPermission(SecurityPermissionFlag.UnmanagedCode)
            sp.Demand()
            AnimateWindow(New HandleRef(control, control.Handle), time, flags)
        Catch generatedExceptionName As SecurityException
        End Try
    End Sub

    <SuppressUnmanagedCodeSecurity> _
    <DllImport("user32.dll", CharSet:=CharSet.Auto, ExactSpelling:=True)> _
    Private Shared Function SetWindowPos(hWnd As HandleRef, hWndInsertAfter As HandleRef, x As Integer, y As Integer, cx As Integer, cy As Integer, _
            flags As Integer) As Boolean
    End Function

    Friend Shared Sub SetTopMost(control As Control)
        Try
            Dim sp As New SecurityPermission(SecurityPermissionFlag.UnmanagedCode)
            sp.Demand()
            SetWindowPos(New HandleRef(control, control.Handle), HWND_TOPMOST, 0, 0, 0, 0, _
                &H13)
        Catch generatedExceptionName As SecurityException
        End Try
    End Sub

    Friend Shared Function HIWORD(n As Integer) As Integer
        Return CShort((n >> 16) And &HFFFF)
    End Function

    Friend Shared Function HIWORD(n As IntPtr) As Integer
        Return HIWORD(CInt(CLng(n)))
    End Function

    Friend Shared Function LOWORD(n As Integer) As Integer
        Return CShort(n And &HFFFF)
    End Function

    Friend Shared Function LOWORD(n As IntPtr) As Integer
        Return LOWORD(CInt(CLng(n)))
    End Function

    <StructLayout(LayoutKind.Sequential)> _
    Friend Structure MINMAXINFO
        Public reserved As Point
        Public maxSize As Size
        Public maxPosition As Point
        Public minTrackSize As Size
        Public maxTrackSize As Size
    End Structure

    Private Shared _isRunningOnMono As System.Nullable(Of Boolean)
    Public Shared ReadOnly Property IsRunningOnMono() As Boolean
        Get
            If Not _isRunningOnMono.HasValue Then
                _isRunningOnMono = Type.[GetType]("Mono.Runtime") IsNot Nothing
            End If
            Return _isRunningOnMono.Value
        End Get
    End Property
End Class

Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Data
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Text
Imports System.Windows.Forms
Imports System.Security.Permissions
Imports System.Runtime.InteropServices
Imports VS = System.Windows.Forms.VisualStyles


<CLSCompliant(True), ToolboxItem(False)> _
Partial Public Class Popup
    Inherits ToolStripDropDown
#Region " Fields & Properties "

    ''' <summary>
    ''' Gets the content of the pop-up.
    ''' </summary>
    Public Property Content() As Control
        Get
            Return m_Content
        End Get
        Private Set(value As Control)
            m_Content = value
        End Set
    End Property
    Private m_Content As Control

    ''' <summary>
    ''' Determines which animation to use while showing the pop-up window.
    ''' </summary>
    Public Property ShowingAnimation() As PopupAnimations
        Get
            Return m_ShowingAnimation
        End Get
        Set(value As PopupAnimations)
            m_ShowingAnimation = value
        End Set
    End Property
    Private m_ShowingAnimation As PopupAnimations

    ''' <summary>
    ''' Determines which animation to use while hiding the pop-up window.
    ''' </summary>
    Public Property HidingAnimation() As PopupAnimations
        Get
            Return m_HidingAnimation
        End Get
        Set(value As PopupAnimations)
            m_HidingAnimation = value
        End Set
    End Property
    Private m_HidingAnimation As PopupAnimations

    ''' <summary>
    ''' Determines the duration of the animation.
    ''' </summary>
    Public Property AnimationDuration() As Integer
        Get
            Return m_AnimationDuration
        End Get
        Set(value As Integer)
            m_AnimationDuration = value
        End Set
    End Property
    Private m_AnimationDuration As Integer

    ''' <summary>
    ''' Gets or sets a value indicating whether the content should receive the focus after the pop-up has been opened.
    ''' </summary>
    ''' <value><c>true</c> if the content should be focused after the pop-up has been opened; otherwise, <c>false</c>.</value>
    ''' <remarks>If the FocusOnOpen property is set to <c>false</c>, then pop-up cannot use the fade effect.</remarks>
    Public Property FocusOnOpen() As Boolean
        Get
            Return m_FocusOnOpen
        End Get
        Set(value As Boolean)
            m_FocusOnOpen = value
        End Set
    End Property
    Private m_FocusOnOpen As Boolean

    ''' <summary>
    ''' Gets or sets a value indicating whether pressing the alt key should close the pop-up.
    ''' </summary>
    ''' <value><c>true</c> if pressing the alt key does not close the pop-up; otherwise, <c>false</c>.</value>
    Public Property AcceptAlt() As Boolean
        Get
            Return m_AcceptAlt
        End Get
        Set(value As Boolean)
            m_AcceptAlt = value
        End Set
    End Property
    Private m_AcceptAlt As Boolean

    Private _host As ToolStripControlHost
    Private _opener As Control
    Private _ownerPopup As Popup
    Private _childPopup As Popup
    Private _resizableTop As Boolean
    Private _resizableLeft As Boolean

    Private _isChildPopupOpened As Boolean
    Private _resizable As Boolean
    ''' <summary>
    ''' Gets or sets a value indicating whether the <see cref="PopupControl.Popup" /> is resizable.
    ''' </summary>
    ''' <value><c>true</c> if resizable; otherwise, <c>false</c>.</value>
    Public Property Resizable() As Boolean
        Get
            Return _resizable AndAlso Not _isChildPopupOpened
        End Get
        Set(value As Boolean)
            _resizable = value
        End Set
    End Property

    Private _nonInteractive As Boolean
    ''' <summary>
    ''' Gets or sets a value indicating whether the <see cref="PopupControl.Popup"></see> acts like a transparent windows (so it cannot be clicked).
    ''' </summary>
    ''' <value>
    ''' <c>true</c> if the popup is noninteractive; otherwise, <c>false</c>.</value>
    Public Property NonInteractive() As Boolean
        Get
            Return _nonInteractive
        End Get
        Set(value As Boolean)
            If value <> _nonInteractive Then
                _nonInteractive = value
                If IsHandleCreated Then
                    RecreateHandle()
                End If
            End If
        End Set
    End Property

    ''' <summary>
    ''' Gets or sets a minimum size of the pop-up.
    ''' </summary>
    ''' <returns>An ordered pair of type <see cref="T:System.Drawing.Size" /> representing the width and height of a rectangle.</returns>
    Public Shadows Property MinimumSize() As Size
        Get
            Return m_MinimumSize
        End Get
        Set(value As Size)
            m_MinimumSize = value
        End Set
    End Property
    Private Shadows m_MinimumSize As Size

    ''' <summary>
    ''' Gets or sets a maximum size of the pop-up.
    ''' </summary>
    ''' <returns>An ordered pair of type <see cref="T:System.Drawing.Size" /> representing the width and height of a rectangle.</returns>
    Public Shadows Property MaximumSize() As Size
        Get
            Return m_MaximumSize
        End Get
        Set(value As Size)
            m_MaximumSize = value
        End Set
    End Property
    Private Shadows m_MaximumSize As Size

    ''' <summary>
    ''' Gets parameters of a new window.
    ''' </summary>
    ''' <returns>An object of type <see cref="T:System.Windows.Forms.CreateParams" /> used when creating a new window.</returns>
    Protected Overrides ReadOnly Property CreateParams() As CreateParams
        <SecurityPermission(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.UnmanagedCode)> _
        Get
            Dim cp As CreateParams = MyBase.CreateParams
            cp.ExStyle = cp.ExStyle Or NativeMethods.WS_EX_NOACTIVATE
            If NonInteractive Then
                cp.ExStyle = cp.ExStyle Or NativeMethods.WS_EX_TRANSPARENT Or NativeMethods.WS_EX_LAYERED Or NativeMethods.WS_EX_TOOLWINDOW
            End If
            Return cp
        End Get
    End Property

#End Region

#Region " Constructors "

    ''' <summary>
    ''' Initializes a new instance of the <see cref="PopupControl.Popup"/> class.
    ''' </summary>
    ''' <param name="content">The content of the pop-up.</param>
    ''' <remarks>
    ''' Pop-up will be disposed immediately after disposion of the content control.
    ''' </remarks>
    ''' <exception cref="T:System.ArgumentNullException"><paramref name="content" /> is <code>null</code>.</exception>
    Public Sub New(content__1 As Control)
        If content__1 Is Nothing Then
            Throw New ArgumentNullException("content")
        End If
        Content = content__1
        FocusOnOpen = True
        AcceptAlt = True
        ShowingAnimation = PopupAnimations.SystemDefault
        HidingAnimation = PopupAnimations.None
        AnimationDuration = 100
        InitializeComponent()
        AutoSize = False
        DoubleBuffered = True
        ResizeRedraw = True
        _host = New ToolStripControlHost(content__1)
        Padding = InlineAssignHelper(Margin, InlineAssignHelper(_host.Padding, InlineAssignHelper(_host.Margin, Padding.Empty)))
        If NativeMethods.IsRunningOnMono Then
            content__1.Margin = Padding.Empty
        End If
        MinimumSize = content__1.MinimumSize
        content__1.MinimumSize = content__1.Size
        MaximumSize = content__1.MaximumSize
        content__1.MaximumSize = content__1.Size
        Size = content__1.Size
        If NativeMethods.IsRunningOnMono Then
            _host.Size = content__1.Size
        End If
        TabStop = InlineAssignHelper(content__1.TabStop, True)
        content__1.Location = Point.Empty
        Items.Add(_host)
        AddHandler content__1.Disposed, Sub(sender, e)
                                            content__1 = Nothing
                                            Dispose(True)
                                        End Sub
        AddHandler content__1.RegionChanged, Sub(sender, e)
                                                 UpdateRegion()
                                             End Sub
        AddHandler content__1.Paint, Sub(sender, e)
                                         PaintSizeGrip(e)
                                     End Sub
        UpdateRegion()
    End Sub

#End Region

#Region " Methods "

    ''' <summary>
    ''' Raises the <see cref="E:System.Windows.Forms.ToolStripItem.VisibleChanged"/> event.
    ''' </summary>
    ''' <param name="e">An <see cref="T:System.EventArgs"/> that contains the event data.</param>
    Protected Overrides Sub OnVisibleChanged(e As EventArgs)
        MyBase.OnVisibleChanged(e)
        If NativeMethods.IsRunningOnMono Then
            Return
        End If
        ' in case of non-Windows
        If (Visible AndAlso ShowingAnimation = PopupAnimations.None) OrElse (Not Visible AndAlso HidingAnimation = PopupAnimations.None) Then
            Return
        End If
        Dim flags As NativeMethods.AnimationFlags = If(Visible, NativeMethods.AnimationFlags.Roll, NativeMethods.AnimationFlags.Hide)
        Dim _flags As PopupAnimations = If(Visible, ShowingAnimation, HidingAnimation)
        If _flags = PopupAnimations.SystemDefault Then
            If SystemInformation.IsMenuAnimationEnabled Then
                If SystemInformation.IsMenuFadeEnabled Then
                    _flags = PopupAnimations.Blend
                Else
                    _flags = PopupAnimations.Slide Or (If(Visible, PopupAnimations.TopToBottom, PopupAnimations.BottomToTop))
                End If
            Else
                _flags = PopupAnimations.None
            End If
        End If
        If (_flags And (PopupAnimations.Blend Or PopupAnimations.Center Or PopupAnimations.Roll Or PopupAnimations.Slide)) = PopupAnimations.None Then
            Return
        End If
        If _resizableTop Then
            ' popup is “inverted”, so the animation must be
            If (_flags And PopupAnimations.BottomToTop) <> PopupAnimations.None Then
                _flags = (_flags And Not PopupAnimations.BottomToTop) Or PopupAnimations.TopToBottom
            ElseIf (_flags And PopupAnimations.TopToBottom) <> PopupAnimations.None Then
                _flags = (_flags And Not PopupAnimations.TopToBottom) Or PopupAnimations.BottomToTop
            End If
        End If
        If _resizableLeft Then
            ' popup is “inverted”, so the animation must be
            If (_flags And PopupAnimations.RightToLeft) <> PopupAnimations.None Then
                _flags = (_flags And Not PopupAnimations.RightToLeft) Or PopupAnimations.LeftToRight
            ElseIf (_flags And PopupAnimations.LeftToRight) <> PopupAnimations.None Then
                _flags = (_flags And Not PopupAnimations.LeftToRight) Or PopupAnimations.RightToLeft
            End If
        End If
        flags = flags Or (NativeMethods.AnimationFlags.Mask And DirectCast(CInt(_flags), NativeMethods.AnimationFlags))
        NativeMethods.SetTopMost(Me)
        NativeMethods.AnimateWindow(Me, AnimationDuration, flags)
    End Sub

    ''' <summary>
    ''' Processes a dialog box key.
    ''' </summary>
    ''' <param name="keyData">One of the <see cref="T:System.Windows.Forms.Keys" /> values that represents the key to process.</param>
    ''' <returns>
    ''' true if the key was processed by the control; otherwise, false.
    ''' </returns>
    <UIPermission(SecurityAction.LinkDemand, Window:=UIPermissionWindow.AllWindows)> _
    Protected Overrides Function ProcessDialogKey(keyData As Keys) As Boolean
        If AcceptAlt AndAlso ((keyData And Keys.Alt) = Keys.Alt) Then
            If (keyData And Keys.F4) <> Keys.F4 Then
                Return False
            Else
                Close()
            End If
        End If
        Dim processed As Boolean = MyBase.ProcessDialogKey(keyData)
        If Not processed AndAlso (keyData = Keys.Tab OrElse keyData = (Keys.Tab Or Keys.Shift)) Then
            Dim backward As Boolean = (keyData And Keys.Shift) = Keys.Shift
            Content.SelectNextControl(Nothing, Not backward, True, True, True)
        End If
        Return processed
    End Function

    ''' <summary>
    ''' Updates the pop-up region.
    ''' </summary>
    Protected Sub UpdateRegion()
        If Region IsNot Nothing Then
            Region.Dispose()
            Region = Nothing
        End If
        If Content.Region IsNot Nothing Then
            Region = Content.Region.Clone()
        End If
    End Sub

    ''' <summary>
    ''' Shows the pop-up window below the specified control.
    ''' </summary>
    ''' <param name="control">The control below which the pop-up will be shown.</param>
    ''' <remarks>
    ''' When there is no space below the specified control, the pop-up control is shown above it.
    ''' </remarks>
    ''' <exception cref="T:System.ArgumentNullException"><paramref name="control"/> is <code>null</code>.</exception>
    Public Overloads Sub Show(control As Control)
        If control Is Nothing Then
            Throw New ArgumentNullException("control")
        End If
        Show(control, control.ClientRectangle)
    End Sub

    ''' <summary>
    ''' Shows the pop-up window below the specified area.
    ''' </summary>
    ''' <param name="area">The area of desktop below which the pop-up will be shown.</param>
    ''' <remarks>
    ''' When there is no space below specified area, the pop-up control is shown above it.
    ''' </remarks>
    Public Overloads Sub Show(ByVal area As Rectangle)
        _resizableTop = InlineAssignHelper(_resizableLeft, False)
        Dim location As New Point(area.Left, area.Top + area.Height)
        Dim screen__1 As Rectangle = Screen.FromControl(Me).WorkingArea
        If location.X + Size.Width > (screen__1.Left + screen__1.Width) Then
            _resizableLeft = True
            location.X = (screen__1.Left + screen__1.Width) - Size.Width
        End If
        If location.Y + Size.Height > (screen__1.Top + screen__1.Height) Then
            _resizableTop = True
            location.Y -= Size.Height + area.Height
        End If
        'location = control.PointToClient(location);
        Show(location, ToolStripDropDownDirection.BelowRight)
    End Sub

    ''' <summary>
    ''' Shows the pop-up window below the specified area of the specified control.
    ''' </summary>
    ''' <param name="control">The control used to compute screen location of specified area.</param>
    ''' <param name="area">The area of control below which the pop-up will be shown.</param>
    ''' <remarks>
    ''' When there is no space below specified area, the pop-up control is shown above it.
    ''' </remarks>
    ''' <exception cref="T:System.ArgumentNullException"><paramref name="control"/> is <code>null</code>.</exception>
    Public Overloads Sub Show(ByVal control As Control, ByVal area As Rectangle)
        If control Is Nothing Then
            Throw New ArgumentNullException("control")
        End If
        SetOwnerItem(control)

        _resizableTop = InlineAssignHelper(_resizableLeft, False)
        Dim location As Point = control.PointToScreen(New Point(area.Left, area.Top + area.Height))
        Dim screen__1 As Rectangle = Screen.FromControl(control).WorkingArea
        If location.X + Size.Width > (screen__1.Left + screen__1.Width) Then
            _resizableLeft = True
            location.X = (screen__1.Left + screen__1.Width) - Size.Width
        End If
        If location.Y + Size.Height > (screen__1.Top + screen__1.Height) Then
            _resizableTop = True
            location.Y -= Size.Height + area.Height
        End If
        location = control.PointToClient(location)
        Show(control, location, ToolStripDropDownDirection.BelowRight)
    End Sub

    Private Sub SetOwnerItem(control As Control)
        If control Is Nothing Then
            Return
        End If
        If TypeOf control Is Popup Then
            Dim popupControl As Popup = TryCast(control, Popup)
            _ownerPopup = popupControl
            _ownerPopup._childPopup = Me
            OwnerItem = popupControl.Items(0)
            Return
        ElseIf _opener Is Nothing Then
            _opener = control
        End If
        If control.Parent IsNot Nothing Then
            SetOwnerItem(control.Parent)
        End If
    End Sub

    ''' <summary>
    ''' Raises the <see cref="E:System.Windows.Forms.Control.SizeChanged" /> event.
    ''' </summary>
    ''' <param name="e">An <see cref="T:System.EventArgs" /> that contains the event data.</param>
    Protected Overrides Sub OnSizeChanged(e As EventArgs)
        If Content IsNot Nothing Then
            Content.MinimumSize = Size
            Content.MaximumSize = Size
            Content.Size = Size
            Content.Location = Point.Empty
        End If
        MyBase.OnSizeChanged(e)
    End Sub

    ''' <summary>
    ''' Raises the <see cref="E:System.Windows.Forms.Control.Layout" /> event.
    ''' </summary>
    ''' <param name="e">A <see cref="T:System.Windows.Forms.LayoutEventArgs" /> that contains the event data.</param>
    Protected Overrides Sub OnLayout(e As LayoutEventArgs)
        If Not NativeMethods.IsRunningOnMono Then
            MyBase.OnLayout(e)
            Return
        End If
        Dim suggestedSize As Size = GetPreferredSize(Size.Empty)
        If AutoSize AndAlso suggestedSize <> Size Then
            Size = suggestedSize
        End If
        SetDisplayedItems()
        OnLayoutCompleted(EventArgs.Empty)
        Invalidate()
    End Sub

    ''' <summary>
    ''' Raises the <see cref="E:System.Windows.Forms.ToolStripDropDown.Opening" /> event.
    ''' </summary>
    ''' <param name="e">A <see cref="T:System.ComponentModel.CancelEventArgs" /> that contains the event data.</param>
    Protected Overrides Sub OnOpening(e As CancelEventArgs)
        If Content.IsDisposed OrElse Content.Disposing Then
            e.Cancel = True
            Return
        End If
        UpdateRegion()
        MyBase.OnOpening(e)
    End Sub

    ''' <summary>
    ''' Raises the <see cref="E:System.Windows.Forms.ToolStripDropDown.Opened" /> event.
    ''' </summary>
    ''' <param name="e">An <see cref="T:System.EventArgs" /> that contains the event data.</param>
    Protected Overrides Sub OnOpened(e As EventArgs)
        If _ownerPopup IsNot Nothing Then
            _ownerPopup._isChildPopupOpened = True
        End If
        If FocusOnOpen Then
            Content.Focus()
        End If
        MyBase.OnOpened(e)
    End Sub

    ''' <summary>
    ''' Raises the <see cref="E:System.Windows.Forms.ToolStripDropDown.Closed"/> event.
    ''' </summary>
    ''' <param name="e">A <see cref="T:System.Windows.Forms.ToolStripDropDownClosedEventArgs"/> that contains the event data.</param>
    Protected Overrides Sub OnClosed(e As ToolStripDropDownClosedEventArgs)
        _opener = Nothing
        If _ownerPopup IsNot Nothing Then
            _ownerPopup._isChildPopupOpened = False
        End If
        MyBase.OnClosed(e)
    End Sub

#End Region

#Region " Resizing Support "

    ''' <summary>
    ''' Processes Windows messages.
    ''' </summary>
    ''' <param name="m">The Windows <see cref="T:System.Windows.Forms.Message" /> to process.</param>
    <SecurityPermission(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.UnmanagedCode)> _
    Protected Overrides Sub WndProc(ByRef m As Message)
        'if (m.Msg == NativeMethods.WM_PRINT && !Visible)
        '{
        '    Visible = true;
        '}
        If InternalProcessResizing(m, False) Then
            Return
        End If
        MyBase.WndProc(m)
    End Sub

    ''' <summary>
    ''' Processes the resizing messages.
    ''' </summary>
    ''' <param name="m">The message.</param>
    ''' <returns>true, if the WndProc method from the base class shouldn't be invoked.</returns>
    <SecurityPermission(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.UnmanagedCode)> _
    Public Function ProcessResizing(ByRef m As Message) As Boolean
        Return InternalProcessResizing(m, True)
    End Function

    <SecurityPermission(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.UnmanagedCode)> _
    Private Function InternalProcessResizing(ByRef m As Message, contentControl As Boolean) As Boolean
        If m.Msg = NativeMethods.WM_NCACTIVATE AndAlso m.WParam <> IntPtr.Zero AndAlso _childPopup IsNot Nothing AndAlso _childPopup.Visible Then
            _childPopup.Hide()
        End If
        If Not Resizable AndAlso Not NonInteractive Then
            Return False
        End If
        If m.Msg = NativeMethods.WM_NCHITTEST Then
            Return OnNcHitTest(m, contentControl)
        ElseIf m.Msg = NativeMethods.WM_GETMINMAXINFO Then
            Return OnGetMinMaxInfo(m)
        End If
        Return False
    End Function

    <SecurityPermission(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.UnmanagedCode)> _
    Private Function OnGetMinMaxInfo(ByRef m As Message) As Boolean
        Dim minmax As NativeMethods.MINMAXINFO = DirectCast(Marshal.PtrToStructure(m.LParam, GetType(NativeMethods.MINMAXINFO)), NativeMethods.MINMAXINFO)
        If Not MaximumSize.IsEmpty Then
            minmax.maxTrackSize = MaximumSize
        End If
        minmax.minTrackSize = MinimumSize
        Marshal.StructureToPtr(minmax, m.LParam, False)
        Return True
    End Function

    Private Function OnNcHitTest(ByRef m As Message, contentControl As Boolean) As Boolean
        If NonInteractive Then
            'm.Result = DirectCast(NativeMethods.HTTRANSPARENT, IntPtr)
            m.Result = New IntPtr(NativeMethods.HTTRANSPARENT)
            Return True
        End If

        Dim x As Integer = Cursor.Position.X
        ' NativeMethods.LOWORD(m.LParam);
        Dim y As Integer = Cursor.Position.Y
        ' NativeMethods.HIWORD(m.LParam);
        Dim clientLocation As Point = PointToClient(New Point(x, y))

        Dim gripBouns As New GripBounds(If(contentControl, Content.ClientRectangle, ClientRectangle))
        Dim transparent As New IntPtr(NativeMethods.HTTRANSPARENT)

        If _resizableTop Then
            If _resizableLeft AndAlso gripBouns.TopLeft.Contains(clientLocation) Then
                'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTTOPLEFT, IntPtr))
                m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTTOPLEFT))
                Return True
            End If
            If Not _resizableLeft AndAlso gripBouns.TopRight.Contains(clientLocation) Then
                'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTTOPRIGHT, IntPtr))
                m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTTOPRIGHT))
                Return True
            End If
            If gripBouns.Top.Contains(clientLocation) Then
                'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTTOP, IntPtr))
                m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTTOP))
                Return True
            End If
        Else
            If _resizableLeft AndAlso gripBouns.BottomLeft.Contains(clientLocation) Then
                'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTBOTTOMLEFT, IntPtr))
                m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTBOTTOMLEFT))
                Return True
            End If
            If Not _resizableLeft AndAlso gripBouns.BottomRight.Contains(clientLocation) Then
                'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTBOTTOMRIGHT, IntPtr))
                m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTBOTTOMRIGHT))
                Return True
            End If
            If gripBouns.Bottom.Contains(clientLocation) Then
                'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTBOTTOM, IntPtr))
                m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTBOTTOM))
                Return True
            End If
        End If
        If _resizableLeft AndAlso gripBouns.Left.Contains(clientLocation) Then
            'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTLEFT, IntPtr))
            m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTLEFT))
            Return True
        End If
        If Not _resizableLeft AndAlso gripBouns.Right.Contains(clientLocation) Then
            'm.Result = If(contentControl, transparent, DirectCast(NativeMethods.HTRIGHT, IntPtr))
            m.Result = If(contentControl, transparent, New IntPtr(NativeMethods.HTRIGHT))
            Return True
        End If
        Return False
    End Function

    Private _sizeGripRenderer As VS.VisualStyleRenderer
    ''' <summary>
    ''' Paints the sizing grip.
    ''' </summary>
    ''' <param name="e">The <see cref="System.Windows.Forms.PaintEventArgs" /> instance containing the event data.</param>
    Public Sub PaintSizeGrip(e As PaintEventArgs)
        If e Is Nothing OrElse e.Graphics Is Nothing OrElse Not _resizable Then
            Return
        End If
        Dim clientSize As Size = Content.ClientSize
        Using gripImage As New Bitmap(&H10, &H10)
            Using g As Graphics = Graphics.FromImage(gripImage)
                If Application.RenderWithVisualStyles Then
                    If _sizeGripRenderer Is Nothing Then
                        _sizeGripRenderer = New VS.VisualStyleRenderer(VS.VisualStyleElement.Status.Gripper.Normal)
                    End If
                    _sizeGripRenderer.DrawBackground(g, New Rectangle(0, 0, &H10, &H10))
                Else
                    ControlPaint.DrawSizeGrip(g, Content.BackColor, 0, 0, &H10, &H10)
                End If
            End Using
            Dim gs As GraphicsState = e.Graphics.Save()
            e.Graphics.ResetTransform()
            If _resizableTop Then
                If _resizableLeft Then
                    e.Graphics.RotateTransform(180)
                    e.Graphics.TranslateTransform(-clientSize.Width, -clientSize.Height)
                Else
                    e.Graphics.ScaleTransform(1, -1)
                    e.Graphics.TranslateTransform(0, -clientSize.Height)
                End If
            ElseIf _resizableLeft Then
                e.Graphics.ScaleTransform(-1, 1)
                e.Graphics.TranslateTransform(-clientSize.Width, 0)
            End If
            e.Graphics.DrawImage(gripImage, clientSize.Width - &H10, clientSize.Height - &H10 + 1, &H10, &H10)
            e.Graphics.Restore(gs)
        End Using
    End Sub
    Private Shared Function InlineAssignHelper(Of T)(ByRef target As T, value As T) As T
        target = value
        Return value
    End Function

#End Region
End Class

<ToolboxBitmap(GetType(System.Windows.Forms.ComboBox)), ToolboxItem(True), ToolboxItemFilter("System.Windows.Forms"), Description("Displays an editable text box with a drop-down list of permitted values.")> _
Partial Public Class PopupComboBox
    Inherits myComboBox
    Public Sub New()
        'this.dropDownHideTime = DateTime.UtcNow;
        InitializeComponent()
        Me.dropDownHideTime = DateTime.UtcNow
        MyBase.DropDownHeight = InlineAssignHelper(MyBase.DropDownWidth, 1)
        MyBase.IntegralHeight = False
    End Sub

    Private _dropDown As PopupControl.Popup
    Private m_dropDownControl As Control

    Public Property DropDownControl() As Control
        Get
            Return m_dropDownControl
        End Get
        Set(value As Control)
            If m_dropDownControl Is value Then
                Return
            End If
            m_dropDownControl = value
            If _dropDown IsNot Nothing Then
                RemoveHandler _dropDown.Closed, AddressOf dropDown_Closed
                _dropDown.Dispose()
            End If
            _dropDown = New Popup(value)
            AddHandler _dropDown.Closed, AddressOf dropDown_Closed
        End Set
    End Property

    Private dropDownHideTime As DateTime
    Private Sub dropDown_Closed(sender As Object, e As ToolStripDropDownClosedEventArgs)
        dropDownHideTime = DateTime.UtcNow
    End Sub

    Public Shadows Property DroppedDown() As Boolean
        Get
            Return _dropDown.Visible
        End Get
        Set(value As Boolean)
            If DroppedDown Then
                HideDropDown()
            Else
                ShowDropDown()
            End If
        End Set
    End Property

    Public Shadows Event DropDown As EventHandler

    Public Sub ShowDropDown()
        If _dropDown IsNot Nothing Then
            If (DateTime.UtcNow - dropDownHideTime).TotalSeconds > 0.5 Then
                RaiseEvent DropDown(Me, EventArgs.Empty)
                _dropDown.Show(Me)
            Else
                dropDownHideTime = DateTime.UtcNow.Subtract(New TimeSpan(0, 0, 1))
                Focus()
            End If
        End If
    End Sub

    Public Shadows Event DropDownClosed As EventHandler

    Public Sub HideDropDown()
        If _dropDown IsNot Nothing Then
            _dropDown.Hide()
            RaiseEvent DropDownClosed(Me, EventArgs.Empty)
        End If
    End Sub

    <SecurityPermission(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.UnmanagedCode)> _
    Protected Overrides Sub WndProc(ByRef m As Message)
        If m.Msg = (NativeMethods.WM_COMMAND + NativeMethods.WM_REFLECT) AndAlso NativeMethods.HIWORD(m.WParam) = NativeMethods.CBN_DROPDOWN Then
            BeginInvoke(New MethodInvoker(AddressOf ShowDropDown))
            Return
        End If
        MyBase.WndProc(m)
    End Sub
End Class