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Imports System.Runtime.InteropServices
'//////////////////////////////////////////////////
<DllImport("winmm.dll", EntryPoint := "mciSendStringA", CharSet := CharSet.Ansi)> _
Protected Shared Function mciSendString(ByVal lpstrCommand As String, ByVal lpstrReturnString As StringBuilder, ByVal uReturnLength As Integer, ByVal hwndCallback As IntPtr) As Integer
End Function

'/******************* OPen **************************\

Dim ret As Integer = mciSendString("set cdaudio door open", Nothing, 0, IntPtr.Zero)

'/******************* Close **************************\

Dim ret As Integer = mciSendString("set cdaudio door closed", Nothing, 0, IntPtr.Zero)
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