static extern Int32 mciSendString(string command, StringBuilder buffer, int bufferSize, IntPtr hwndCallback);

Private Shared Function mciSendString(ByVal command As String, ByVal buffer As StringBuilder, ByVal bufferSize As Integer, ByVal hwndCallback As IntPtr) As Integer

Declare Ansi Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal command As String, ByRef buffer As StringBuilder, ByVal bufferSize As Integer, ByVal hWndCallback As IntPtr) As Integer

    mciSendString("set CDAudio door open", returnstring,127, IntPtr.Zero);

mciSendString(sCommand, null, 0, 0);

mciSendString(sCommand, null, 0, _frmObject.Handle.ToInt64());

static extern Int32 mciSendString(string command, string buffer, int bufferSize, IntPtr hwndCallback);

     mciSendString("set CDAudio door open", rt, 127, IntPtr.Zero);

     mciSendString("set CDAudio door closed", rt, 127, IntPtr.Zero);

     mciSendString("set CDAudio door open", returnstring, 127, IntPtr.Zero)

     mciSendString(sCommand, Nothing, 0, IntPtr.Zero)

     mciSendString(sCommand, Nothing, 0, Me.Handle.ToInt64())