public static void Export(InternalFormat data)
        {
            var App = new Excel.Application();

            // Make the object visible.
            App.Visible = true;
            // App.ScreenUpdating = false;

            // Create a new, empty workbook and add it to the collection returned
            // by property Workbooks. The new workbook becomes the active workbook.
            // Add has an optional parameter for specifying a praticular template.
            // Because no argument is sent in this example, Add creates a new workbook.
            var Workbooks = App.Workbooks;

            Workbooks.Add();

            // This example uses a single workSheet.
            Excel._Worksheet Worksheet = App.ActiveSheet;

            // Caption
            Worksheet.Rows[1].Interior.Color      = ColorTranslator.ToOle(Color.Orange);
            Worksheet.Rows[1].Font.Bold           = true;
            Worksheet.Rows[1].HorizontalAlignment = Excel.XlHAlign.xlHAlignCenter;

            // Establish column headings in cells A1, B1 and other.
            Worksheet.Columns[1].ColumnWidth = 10;
            Worksheet.Cells[1, "A"]          = "#";
            Worksheet.Columns[2].ColumnWidth = 40;
            Worksheet.Cells[1, "B"]          = "ID";
            Worksheet.Columns[3].ColumnWidth = 100;
            Worksheet.Cells[1, "C"]          = data.NativeCulture;
            for (int i = 0, j = 4; i < data.Cultures.Count; i++)
            {
                if (data.Cultures[i] == data.NativeCulture)
                {
                    continue;
                }
                Worksheet.Columns[j].ColumnWidth = 100;
                Worksheet.Cells[1, j]            = data.Cultures[i];
                j++;
            }

            int index = 2;

            foreach (var ns in data.Subnamespaces)
            {
                foreach (var rec in ns.Children)
                {
                    foreach (var key in rec.Keys)
                    {
                        Worksheet.Cells[index, "A"].HorizontalAlignment = Excel.XlHAlign.xlHAlignCenter;
                        Worksheet.Cells[index, "A"] = (index - 1).ToString();
                        Worksheet.Cells[index, "B"] = InternalNamespace.MakeFullName(ns.Name, key.Key);
                        Worksheet.Cells[index, "C"].Interior.Color = ColorTranslator.ToOle(Color.FromArgb(255, 229, 212));
                        Worksheet.Cells[index, "C"] = key.GetTranslationForCulture(data.NativeCulture);
                        for (int i = 0, j = 4; i < data.Cultures.Count; i++)
                        {
                            if (data.Cultures[i] == data.NativeCulture)
                            {
                                continue;
                            }
                            Worksheet.Cells[index, j].Interior.Color = (j % 2 == 0) ?
                                                                       ColorTranslator.ToOle(Color.FromArgb(200, 239, 212)) :
                                                                       ColorTranslator.ToOle(Color.FromArgb(200, 235, 250));
                            Worksheet.Cells[index, j] = key.GetTranslationForCulture(data.Cultures[i]);
                            j++;
                        }
                        index++;
                    }
                }
            }

            Worksheet.Cells[index, "A"].Font.Color = ColorTranslator.ToOle(Color.Red);
            Worksheet.Cells[index, "A"].Font.Bold  = true;
            Worksheet.Cells[index, "A"]            = serviceData;
            index++;

            foreach (var ns in data.Subnamespaces)
            {
                foreach (var rec in ns.Children)
                {
                    foreach (var key in rec.Keys)
                    {
                        Worksheet.Rows[index].Font.Color = ColorTranslator.ToOle(Color.LightGray);
                        Worksheet.Cells[index, "A"]      = rec.Source;
                        Worksheet.Cells[index, "B"]      = ns.Name;
                        Worksheet.Cells[index, "C"]      = key.Key;
                        Worksheet.Cells[index, "D"]      = key.Path;
                        index++;
                    }
                }
            }

            // App.ScreenUpdating = true;

            Marshal.ReleaseComObject(Worksheet); Worksheet = null;
            Marshal.ReleaseComObject(Workbooks); Workbooks = null;
            Marshal.ReleaseComObject(App); App             = null;
        }
        public static InternalFormat Import(string FileName)
        {
            InternalFormat data = null;

            // open excel document
            Excel.Application App       = new Excel.Application();
            Excel.Workbooks   Workbooks = App.Workbooks;
            Excel.Workbook    Workbook  = Workbooks.Open(FileName);
            Excel._Worksheet  Worksheet = App.ActiveSheet;
            Excel.Range       Range     = Worksheet.UsedRange;

            // read document data

            var Cells       = Range.Value2;
            int rowCount    = Cells.GetLength(0);
            int columnCount = Cells.GetLength(1);

            data = new InternalFormat();

            // read native and other cultures
            data.Cultures = new List <string>();
            for (int col = 3; col <= columnCount; col++)
            {
                if (Cells[1, col] != null)
                {
                    // third column is NativeCulture
                    if (col == 3)
                    {
                        data.NativeCulture = Cells[1, col];
                    }
                    data.Cultures.Add(Cells[1, col]);
                }
            }

            int index               = 2;
            int cultureCount        = data.Cultures.Count;
            List <InternalKey> keys = new List <InternalKey>(rowCount / 2);

            // read all translation keys
            for (; Cells[index, 1].ToString() != serviceData; index++)
            {
                InternalKey key = new InternalKey();
                key.Key          = InternalNamespace.SplitFullName(Cells[index, 2])[1];
                key.Translations = new List <InternalText>(cultureCount);
                for (int culture = 0; culture < cultureCount; culture++)
                {
                    InternalText translation = new InternalText();
                    translation.Culture = data.Cultures[culture];
                    translation.Text    = Cells[index, culture + 3];
                    if (translation.Text == null)
                    {
                        translation.Text = "";
                    }
                    else // replace \n to \r\n
                    {
                        translation.Text = Regex.Replace(translation.Text, "(?<!\r)\n", "\r\n");
                    }
                    key.Translations.Add(translation);
                }
                keys.Add(key);
            }

            int indexOfServiceData = index;

            data.Subnamespaces = new List <InternalNamespace>(rowCount / 2);
            InternalNamespace lastNS  = null;
            InternalRecord    lastRec = null;

            index++;
            for (; index < rowCount + 1; index++)
            {
                string source = Cells[index, 1];
                string ns     = Cells[index, 2];
                string key    = Cells[index, 3];
                string path   = Cells[index, 4];

                if (lastNS == null || lastNS.Name != ns)
                {
                    lastNS          = new InternalNamespace();
                    lastNS.Name     = ns;
                    lastNS.Children = new List <InternalRecord>();
                    data.Subnamespaces.Add(lastNS);
                    lastRec = null;
                }

                if (lastRec == null || lastRec.Source != source)
                {
                    lastRec        = new InternalRecord();
                    lastRec.Source = source;
                    lastRec.Keys   = new List <InternalKey>();
                    lastNS.Children.Add(lastRec);
                }

                InternalKey ikey = keys[index - indexOfServiceData - 1];
                if (ikey.Key != key)
                {
                    throw new FormatException("Unexpected key: " + key + "!");
                }

                ikey.Path   = path;
                ikey.parent = lastRec;
                lastRec.Keys.Add(ikey);
            }

            // close excel and clear all headres
            Marshal.ReleaseComObject(Range); Range         = null;
            Marshal.ReleaseComObject(Worksheet); Worksheet = null;
            Workbook.Close(false, Type.Missing, Type.Missing);
            Marshal.ReleaseComObject(Workbook); Workbook = null;
            Workbooks.Close();
            Marshal.ReleaseComObject(Workbooks); Workbooks = null;
            App.Quit();
            Marshal.ReleaseComObject(App); App = null;

            return(data);
        }