public string CalculateETag(FileInfo file) { var material = new StringBuilder(); material.AppendLine(file.FullName); material.AppendLine(file.LastWriteTime.Ticks.ToString()); material.AppendLine(file.Length.ToString()); var hash = m_hashAlgorithm.ComputeHash(Encoding.UTF8.GetBytes(material.ToString())); return(ETagUtil.CreateWeakETag(new string( hash.SelectMany(b => b.ToString("x2").ToLower()).ToArray()))); }