OpenXML SDK Sample: Find and replace marks with text

OpenXMLSample.cs

using System;
using System.Collections.Generic;
using System.Linq;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Spreadsheet;

namespace OpenXML_ReadAndReplaceMarks
{
    class Program
    {
        private static readonly char markSymbol = '$';
        private static readonly string filePath = @"d:\test.xlsx";
        static void Main( string[] args)
        {
            using (SpreadsheetDocument spreadsheetDocument = SpreadsheetDocument.Open(filePath, true ))
            {
                WorkbookPart workbookPart = spreadsheetDocument.WorkbookPart;
                WorksheetPart worksheetPart = workbookPart.WorksheetParts.First();
                SharedStringTablePart stringTablePart = workbookPart.SharedStringTablePart;
                SharedStringTable stringTable = stringTablePart.SharedStringTable;
                IEnumerable<SharedStringItem> values = stringTable.Elements<SharedStringItem>();

                foreach ( var entry in values)
                {
                    if (entry.Text.Text.First() != markSymbol
                        || entry.Text.Text.Last() != markSymbol
                        || String.IsNullOrEmpty(entry.Text.Text))
                        continue;

                    switch (entry.Text.Text.ToUpper())
                    {
                        // Имя абонента:
                        case "$NAME$":
                            entry.Text.Text = "Иван";
                            continue;
                        // Фамилия абонента:
                        case "$SURNAME$":
                            entry.Text.Text = "Грозный" ;
                            continue;
                        // Мобильный телефон:
                        case "$PHONE$":
                            entry.Text.Text = "03";
                            continue;
                        // Электронная почта:
                        case "$MAIL$":
                            entry.Text.Text = "царь@всеяруси.рф" ;
                            continue;
                        // Город регистрации:
                        case "$REGISTRATION$":
                            entry.Text.Text = "Кремль" ;
                            continue;
                        default:
                            throw new NotImplementedException("Unrecognized text mark: " + entry.Text.Text + Environment.NewLine + "Should be implemented in switch case!");
                    }
                }
                workbookPart.Workbook.Save();
                spreadsheetDocument.Close();
            }
        }
    }
}