I’m converting a byte file from Delphi 1, to Delphi Firemonkey.
I’m very confused with the behaviour of TFileStream.
I have a record structure, with fixed width strings in it, and various other data-structures, array (from Delphi 1).
When I read in the file into a TFileStream using Read, and a size of the record structure, the record structure does not return the right result.
However, when I read in the individual fields one-by-one, using the same method it works.
I cannot figure this out.
Example.
This doesn’t work in Firemonkey (It does work in Delphi 1).
fs.read(Project , Sizeof(Project );
This code does work in firemonkey.
fs.Read(project.name, Sizeof(Name));
fs.Read(Project.date, Sizeof(date)); etc,etc,etc
What’s the difference? The original file is ANSI encoding. The only difference between the record structures is that Integers are now smallints.
Pretty baffled at the moment.
Answer — is to ensure in my case that every single array, and record structure was ‘packed’. I don’t fully understand the alignment of record structures/array in Delphi Seattle (or Delphi 1, for that matter), it has something to do with record alignment, but my code is now back to read(record, sizeof(record). Good!
