Microsoft.VisualStudio.Project.UnsafeNativeMethods.DragQueryFile C# (CSharp) Method

        internal static extern uint DragQueryFile(IntPtr hDrop, uint iFile, char[] lpszFile, uint cch);

        /// <summary>
        /// Retrives data from a VS format.
        /// </summary>
        public static List <string> GetDroppedFiles(ushort format, Microsoft.VisualStudio.OLE.Interop.IDataObject dataObject, out DropDataType ddt)
        {
            ddt = DropDataType.None;
            List <string> droppedFiles = new List <string>();

            ThreadHelper.ThrowIfNotOnUIThread();

            // try HDROP
            FORMATETC fmtetc = CreateFormatEtc(format);

            if (QueryGetData(dataObject, ref fmtetc) == VSConstants.S_OK)
            {
                STGMEDIUM stgmedium = DragDropHelper.GetData(dataObject, ref fmtetc);
                if (stgmedium.tymed == (uint)TYMED.TYMED_HGLOBAL)
                {
                    // We are releasing the cloned hglobal here.
                    IntPtr dropInfoHandle = stgmedium.unionmember;
                    if (dropInfoHandle != IntPtr.Zero)
                    {
                        ddt = DropDataType.Shell;
                        try
                        {
                            uint numFiles = UnsafeNativeMethods.DragQueryFile(dropInfoHandle, 0xFFFFFFFF, null, 0);

                            // We are a directory based project thus a projref string is placed on the clipboard.
                            // We assign the maximum length of a projref string.
                            // The format of a projref is : <Proj Guid>|<project rel path>|<file path>
                            uint   lenght  = (uint)Guid.Empty.ToString().Length + 2 * NativeMethods.MAX_PATH + 2;
                            char[] moniker = new char[lenght + 1];
                            for (uint fileIndex = 0; fileIndex < numFiles; fileIndex++)
                            {
                                uint   queryFileLength = UnsafeNativeMethods.DragQueryFile(dropInfoHandle, fileIndex, moniker, lenght);
                                string filename        = new String(moniker, 0, (int)queryFileLength);
                                droppedFiles.Add(filename);
                            }
                        }
                        finally
                        {
                            Marshal.FreeHGlobal(dropInfoHandle);
                        }
                    }
                }
            }

            return(droppedFiles);
        }