Auto-close message box

Imports System.Runtime.InteropServices

Public Class Form1

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Private Shared Function FindWindow(ByVal lpClassName As String, ByVal lpWindowName As String) As IntPtr
End Function
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Public Shared Function PostMessage(ByVal hWnd As IntPtr, ByVal msg As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
End Function
Public Const WM_CLOSE As Integer = &H10
Private Sub StartKiller()
Dim timer As New Timer()
timer.Interval = 3000 '3秒啓動
AddHandler timer.Tick, AddressOf Timer_Tick
timer.Start()
End Sub

Private Sub KillMessageBox()
'依MessageBox的標題,找出MessageBox的視窗
Dim ptr As IntPtr = FindWindow(Nothing, "TEST")
If ptr <> IntPtr.Zero Then '找到則關閉MessageBox視窗
PostMessage(ptr, WM_CLOSE, IntPtr.Zero, IntPtr.Zero)
End If
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
StartKiller()
MessageBox.Show("3秒後自動關閉訊息視窗", "TEST")
End Sub
Private Sub Timer_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) KillMessageBox()
CType(sender, Timer).Stop()
End Sub

End Class