I have a C# project in which i use several unmanaged C++ functions. More so, I also have static IntPtr that I use as parameters for those functions. I know that whenever I use them, I should implement IDisposable in that class and use a destructor to invoke the Dispose method, where I free the used IntPtr, as is said in the MSDN page.

    public void Dispose()
    {
        Dispose(true);
        GC.SuppressFinalize(this);
    }

    private void Dispose(bool disposing)
    {
        // Check to see if Dispose has already been called.
        if (!this.disposed)
        {
            if (disposing)
            {
                component.Dispose();
            }

            CloseHandle(m_InstanceHandle);
            m_InstanceHandle = IntPtr.Zero;

            disposed = true;

        }
    }

    [System.Runtime.InteropServices.DllImport("Kernel32")]
    private extern static Boolean CloseHandle(IntPtr handle);

However, when I terminate the application, I'm still left with a hanging process in TaskManager. I believe that it must be related to the used of the MarshalAs instruction in my structures:

 [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
 public struct SipxAudioCodec
 {
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst=32)]
        public string CodecName;
        public SipxAudioBandwidth Bandwidth;
        public int PayloadType;
 }

When I create such a structure should I also be careful to free the space it allocs using a destructor?

 [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
 public struct SipxAudioCodec
 {
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst=32)]
        public string CodecName;
        public SipxAudioBandwidth Bandwidth;
        public int PayloadType;

        ~SipxAudioCodec()
        {
            Marshal.FreeGlobal(something...);
        }
 }

Thanks in advance!