Calculate field offset in a typed record

From: Rudi Loos (loos_at_intekom.co.za)
Date: 12/29/03

  • Next message: KLinZ: "Re: Calculate field offset in a typed record" 
    Date: Mon, 29 Dec 2003 02:42:00 +0200

    Hi

    I have looked on the web and in the groups but to no avail. Can anyone
    explain how I can calculate the offset of a field with respect to the
    record. e.g.:

     TMyrecord = packed record
        Field1 : Integer;
        Field2 : Array [0..25] of byte;
        ......
        Field24 : Word;
        Field25 : String[13]
     end;

    I would like to calculate the offset to field24 with respect to MyRecord.
    I have large records that I use to communicate with an electronic device and
    want to pass an address and byte count so that I will only need to read 2
    bytes at address Field24.
    I tried to subtract the pointers but I get an error "operation not
    applicable"

    Thanks to everyone in the group that continually provides help.

    Rudi

  • Next message: KLinZ: "Re: Calculate field offset in a typed record"

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