BuildDTOsFromExcel.FileService.FileParser.Parse C# (CSharp) Method

        public List<string> Parse(List<string> files)
        {
            List<string> filesWithSearchPattern = files.FindAll(x => x.Contains(XlsSearchPattern) || x.Contains(XlsxSearchPattern));
            List<string> completeListOfFiles = files.FindAll(x => !x.Contains(XlsSearchPattern) && !x.Contains(XlsxSearchPattern));
            foreach (string file in filesWithSearchPattern)
            {
                completeListOfFiles.AddRange(GetFiles(file));
            }
            return completeListOfFiles;
        }