Solved

Binary Error Record

Posted on 1997-05-05
1
147 Views
Last Modified: 2010-04-06
When runnning the Linklst2.dpr, why does Delphi 1.0 create such a big binary record file eg: the binary file size is
LINKEXP .DTA   51,282 .a.. 02-05-97  7:14:10 pm
from such a small bunch of records (100 records), when using all your default settings in the link list demo?

After making a copy of the above program, I changed the total records to 3000 and the binary file size blew out to >1.5M in size.

Whats happening and why?

How can I limit the binary file to its logical smallest size?

*******************

const
  Max = 100; {max records for text file, therefore max linked list size}

Record Structure

type
  PMyNode = ^TMyNode;
  TMyNode = record
    Name  : String;
    Flight: integer;
    Day   : String;
    Next  : PMyNode;  {Used to link each field}
  end;

sample of the write procedure

procedure TDataForm.CreateNewFile;
var
  F: File of TMyNode;
  Head: PMyNode;
begin
  Head := FirstNode;
  System.Assign(F, FileName);
  ReWrite(F);
  while Head^.Next <> nil do begin
    System.Write(F, Head^);
    Head := Head^.Next;
  end;
  Write(F, Head^);
  System.Close(F);
end;


*******************

sample dump of the LINKEXP .DTA when viewed from within xtree, showing other data that is most likely not directly related to the record structure but added by delphi.

 009640   ·tkUnknown·tkInteger·tkChar·tkEnumeration·tkFloat·tkString·tkSet
 009680   ·tkClass·tkMethod··TTypeKinds·······TOrdType··············otL··S
 0096C0   aturdayte·otSWord·otUWord·otSLong··TFloatType··············ftSin
 009700   gle·ftDouble·ftExtended·ftComp·ftReal··TMethodKind··············
 009740   mkProcedure·mkFunction··TPropInfoProc····PropInfo·PPropInfoU···~
 009780   ·&·]····A·······U···~·1·&·]·&·y·&·]··y··N···&···y···········U·\·
 0097C0   ·G·Sam771··\··p··\··P··p·BR··8·t··p·Ju·X·····WV····FG··&2·$·u·Iu
 009800   ·^_u·X)·······U·····~·&······v··\····p··\··P···t··x··]····9·t···
 009840   ·y·Ju··t·····u·1···#WV·u··~···0·FG·<&2=···u·Iu·^_u··········U···

0
Comment
Question by:Darryl050597
1 Comment
 
LVL 3

Accepted Solution

by:
sperling earned 100 total points
ID: 1335915
A string is 256 bytes, therefore your record is 514 bytes.

100*514

Use e.g. string[20] in your record declaration.


Regards,

Erik.
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

The uses clause is one of those things that just tends to grow and grow. Most of the time this is in the main form, as it's from this form that all others are called. If you have a big application (including many forms), the uses clause in the in…
In this tutorial I will show you how to use the Windows Speech API in Delphi. I will only cover basic functions such as text to speech and controlling the speed of the speech. SAPI Installation First you need to install the SAPI type library, th…
This is used to tweak the memory usage for your computer, it is used for servers more so than workstations but just be careful editing registry settings as it may cause irreversible results. I hold no responsibility for anything you do to the regist…
Learn how to create flexible layouts using relative units in CSS.  New relative units added in CSS3 include vw(viewports width), vh(viewports height), vmin(minimum of viewports height and width), and vmax (maximum of viewports height and width).

895 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

16 Experts available now in Live!

Get 1:1 Help Now