'Beispiel: VB .Net - Uhr im Systray - Verstecken / anzeigen ' Option Explicit On Option Strict On Imports System.Runtime.InteropServices Public Class Form1 Private hs As HideOrShowClock Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _ Handles Button1.Click Dim Handle As IntPtr = Systray.GetHandle If Not Handle.Equals(IntPtr.Zero) Then hs = New HideOrShowClock(1, Handle) If hs IsNot Nothing Then Dim Result As Integer = hs.HideOrShow() Me.Text = result.ToString() End If End If End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _ Handles Button2.Click Dim Handle As IntPtr = Systray.GetHandle If Not Handle.Equals(IntPtr.Zero) Then hs = New HideOrShowClock(2, Handle) If hs IsNot Nothing Then Dim Result As Integer = hs.HideOrShow() Me.Text = result.ToString() End If End If End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _ Handles MyBase.Load Me.CenterToScreen() End Sub End Class Public Class Systray <DllImport("user32.dll", EntryPoint:="FindWindow")> _ Private Shared Function FindWindow(ByVal ClassName As String, ByVal WindowName As String) As IntPtr End Function <DllImport("user32.dll", CharSet:=CharSet.Auto, SetLastError:=True)> _ Private Shared Function FindWindowEx( _ ByVal hwndParent As IntPtr, _ ByVal hwndChildAfter As IntPtr, _ ByVal lpszClass As String, _ ByVal lpszWindow As String) As IntPtr End Function Public Shared Function GetHandle() As IntPtr Dim hWnd As IntPtr = FindWindow("Shell_TrayWnd", Nothing) If Not hWnd.Equals(IntPtr.Zero) Then hWnd = FindWindowEx(hWnd, IntPtr.Zero, "TrayNotifyWnd", Nothing) If Not hWnd.Equals(IntPtr.Zero) Then hWnd = FindWindowEx(hWnd, IntPtr.Zero, "TrayClockWClass", Nothing) If Not hWnd.Equals(IntPtr.Zero) Then Return hWnd Else Return IntPtr.Zero End If Else Return IntPtr.Zero End If Else Return IntPtr.Zero End If Return IntPtr.Zero End Function End Class Public Class HideOrShowClock Private Const SW_HIDE As Integer = 0 Private Const SW_SHOW As Integer = 5 'Return Value 'If the window was previously visible, the return value is nonzero. 'If the window was previously hidden, the return value is zero. <DllImport("user32.dll", EntryPoint:="ShowWindow")> _ Private Shared Function ShowWindow(ByVal hWnd As IntPtr, ByVal nCmdShow As Integer) As Integer End Function Private _index As Integer Private _handle As IntPtr Public Sub New(ByVal Index As Integer, ByVal Handle As IntPtr) Me._index = Index Me._handle = Handle End Sub Public Function HideOrShow() As Integer Dim Result As Integer Select Case Me._index Case 1 ' Hide Result = ShowWindow(Me._handle, SW_HIDE) Return Result Case 2 ' Show Result = ShowWindow(Me._handle, SW_SHOW) Return Result Case Else Return -1 End Select End Function End Class