private List<DsObjectPickerItem> ProcessSelections(System.Runtime.InteropServices.ComTypes.IDataObject dataObj)
        {
            List<DsObjectPickerItem> selections = new List<DsObjectPickerItem>();

            if (dataObj == null)
            {
                return selections;
            }

            STGMEDIUM stg = new STGMEDIUM();
            stg.tymed = TYMED.TYMED_HGLOBAL;
            stg.unionmember = IntPtr.Zero;
            stg.pUnkForRelease = null;

            FORMATETC fe = new FORMATETC();
            if (!this.DesignMode)
            {
                fe.cfFormat = (short)System.Windows.Forms.DataFormats.GetFormat(CfstrDsopDsSelectionList).Id;
            }
            fe.ptd = IntPtr.Zero;
            fe.dwAspect = DVASPECT.DVASPECT_CONTENT;
            fe.lindex = -1;
            fe.tymed = TYMED.TYMED_HGLOBAL;

            dataObj.GetData(ref fe, out stg);

            IntPtr pDsSL = UnsafeNativeMethods.GlobalLock(stg.unionmember);

            try
            {
                IntPtr current = pDsSL;
                int cnt = Marshal.ReadInt32(current);

                if (cnt > 0)
                {
                    current = (IntPtr)((int)current + (Marshal.SizeOf(typeof(uint)) * 2));
                    for (int i = 0; i < cnt; i++)
                    {
                        UnsafeNativeMethods.DsSelection selection =
                            (UnsafeNativeMethods.DsSelection)Marshal.PtrToStructure(current,
                            typeof(UnsafeNativeMethods.DsSelection));
                        Marshal.DestroyStructure(current, typeof(UnsafeNativeMethods.DsSelection));

                        current = (IntPtr)((int)current + Marshal.SizeOf(typeof(UnsafeNativeMethods.DsSelection)));

                        DsObjectPickerItem item = new DsObjectPickerItem();
                        item.Name = selection.pwzName;
                        item.Upn = GetUpnFromSelection(selection);
                        item.ClassName = selection.pwzClass.ToLowerInvariant();
                        item.Sid = GetSidFromUpn(item.Upn);
                        selections.Add(item);
                    }
                }
            }
            finally
            {
                if (stg.unionmember != IntPtr.Zero)
                {
                    UnsafeNativeMethods.GlobalUnlock(stg.unionmember);
                }
                UnsafeNativeMethods.ReleaseStgMedium(ref stg);
            }

            return selections;
        }
        private List <DsObjectPickerItem> ProcessSelections(System.Runtime.InteropServices.ComTypes.IDataObject dataObj)
        {
            List <DsObjectPickerItem> selections = new List <DsObjectPickerItem>();

            if (dataObj == null)
            {
                return(selections);
            }

            STGMEDIUM stg = new STGMEDIUM();

            stg.tymed          = TYMED.TYMED_HGLOBAL;
            stg.unionmember    = IntPtr.Zero;
            stg.pUnkForRelease = null;

            FORMATETC fe = new FORMATETC();

            if (!this.DesignMode)
            {
                fe.cfFormat = (short)System.Windows.Forms.DataFormats.GetFormat(CfstrDsopDsSelectionList).Id;
            }
            fe.ptd      = IntPtr.Zero;
            fe.dwAspect = DVASPECT.DVASPECT_CONTENT;
            fe.lindex   = -1;
            fe.tymed    = TYMED.TYMED_HGLOBAL;

            dataObj.GetData(ref fe, out stg);

            IntPtr pDsSL = UnsafeNativeMethods.GlobalLock(stg.unionmember);

            try
            {
                IntPtr current = pDsSL;
                int    cnt     = Marshal.ReadInt32(current);

                if (cnt > 0)
                {
                    current = (IntPtr)((int)current + (Marshal.SizeOf(typeof(uint)) * 2));
                    for (int i = 0; i < cnt; i++)
                    {
                        UnsafeNativeMethods.DsSelection selection =
                            (UnsafeNativeMethods.DsSelection)Marshal.PtrToStructure(current,
                                                                                    typeof(UnsafeNativeMethods.DsSelection));
                        Marshal.DestroyStructure(current, typeof(UnsafeNativeMethods.DsSelection));

                        current = (IntPtr)((int)current + Marshal.SizeOf(typeof(UnsafeNativeMethods.DsSelection)));

                        DsObjectPickerItem item = new DsObjectPickerItem();
                        item.Name      = selection.pwzName;
                        item.Upn       = GetUpnFromSelection(selection);
                        item.ClassName = selection.pwzClass.ToLowerInvariant();
                        item.Sid       = GetSidFromUpn(item.Upn);
                        selections.Add(item);
                    }
                }
            }
            finally
            {
                if (stg.unionmember != IntPtr.Zero)
                {
                    UnsafeNativeMethods.GlobalUnlock(stg.unionmember);
                }
                UnsafeNativeMethods.ReleaseStgMedium(ref stg);
            }

            return(selections);
        }