Reading and writing variants.

Posted on 1998-05-11
Medium Priority
Last Modified: 2010-04-06
I'm overriding the define properties method of a number of classes to stream my own classes into a file stream.  I create the TReaderProc and TWriterProc for each property and use Reader.ReadString, ReadInteger etc.  My only problem is that I have some variant properties which I need to store in the stream, and there is no ReadVariant and WriteVariant methods.  How do I read and write variants to and from the stream.  The variants are variant arrays of byte.


Question by:BigMadDrongo
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Accepted Solution

JimBob091197 earned 400 total points
ID: 1344204

You could use a method similar to TStrings, except that you write one byte at a time from the array, instead of one string at a time like TStrings.

The writer would look like this:
  for I := 0 to Count - 1 do Writer.WriteChar(Chr(YourArr[I]));

The reader would look like this:
  while not Reader.EndOfList do begin
    NextCh := Reader.ReadChar;
    // Do something with NextCh, e.g. add NextCh to your array...

You could use TReader.Read and TWriter.Write, but Delphi doesn't recommend this method...


Author Comment

ID: 1344205
Cheers for you help.


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