private void ReadContents(string filePath)
{
this.filePath = filePath;
DecompressFolder = Path.GetTempFileName() + @"_excelutility\";
Directory.CreateDirectory(DecompressFolder);
new FastZip().ExtractZip(filePath, DecompressFolder, null);
var contentTypesData = new XElementData(XDocument.Load(string.Format("{0}[Content_Types].xml", DecompressFolder)).Root);
contentTypes = new ContentTypes(contentTypesData);
sharedStrings = new SharedStrings(DecompressFolder + contentTypes.GetSharedStringsPath());
workbook = new Workbook(DecompressFolder, contentTypes, sharedStrings);
}