private static String ReadPdf(String fileName)
        {



            Stream stream =new FileStream(fileName, FileMode.Open, FileAccess.Read);
            Byte[] buffer = new Byte[stream.Length];
            stream.Read(buffer,0,Convert.ToInt32(stream.Length));
        
            StringBuilder sb = new StringBuilder();
           
            CSequence sequence = ContentReader.ReadContent(buffer);
               
            sb.Append(Encoding.Unicode.GetString(sequence.ToContent()));
         
            return sb.ToString();
        }