public override ArcFile TryOpen(ArcView file) { int version = file.View.ReadByte(4) * 10 + file.View.ReadByte(5) - '0' * 11; if (file.View.ReadByte(6) != 0 || version < 10 || version > 12) { return(null); } using (var reader = new AbmpReader(file, version)) { var dir = reader.ReadIndex(); if (null == dir || 0 == dir.Count) { return(null); } return(new ArcFile(file, this, dir)); } }