public ImmutableList <byte> GetNewTextId(ChromGroupHeaderInfo chromGroupHeaderInfo) { byte[] textIdBytes = _originalCache.GetTextIdBytes(chromGroupHeaderInfo.TextIdIndex, chromGroupHeaderInfo.TextIdLen); if (textIdBytes == null) { return(null); } const CacheFormatVersion versionNewTextId = CacheFormatVersion.Thirteen; ImmutableList <byte> newTextId; if (_originalCache.Version < versionNewTextId || _cacheFormat.FormatVersion >= versionNewTextId) { newTextId = ImmutableList.ValueOf(textIdBytes); } else { if (textIdBytes[0] == '#') { newTextId = ImmutableList.ValueOf(textIdBytes); } else { var oldKey = new PeptideLibraryKey(Encoding.UTF8.GetString(textIdBytes), 0); var newKey = oldKey.FormatToOneDecimal(); newTextId = ImmutableList.ValueOf(Encoding.UTF8.GetBytes(newKey.ModifiedSequence)); } } return(newTextId); }