The sort is called for you by the TList sort routine. Your function does the
sort of 2 items the TList Sort calls your function repeatedly passing
different items - 2 items at a time to compare.
basically the TList does the Sort for you - you just tell it how to know
which of 2 items is "bigger".
Regards
Paul
[EMAIL PROTECTED]
(Wellington - New Zealand)
-----Original Message-----
From: Coulter, Jeremy [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, 17 November 1999 10:56 AM
To: Multiple recipients of list delphi
Subject: RE: [DUG]: Sorting
ok, that does look simple enought, BUT you say you do
"Mylist.Sort(ItemsCompare);" yet part of the function
"function ItemsCompare(Item1, Item2: Pointer): Integer;" it requires 2 items
to be passed to it.
so, would it not be "Mylist.Sort(ItemsCompare(theItem1,TheItem2 ));"??
Jeremy Coulter
Application Developer
Application Development Centre
Compaq Computer New Zealand Ltd.
Phone: 64 3 371 5724
Fax: 64 3 371 5724
Mobile: 64 0212533214
E-mail: [EMAIL PROTECTED]
Personal Email: [EMAIL PROTECTED]
-----Original Message-----
From: Neven MacEwan [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, November 17, 1999 10:26 AM
To: Multiple recipients of list delphi
Subject: Re: [DUG]: Sorting
Jeremy
It quite simple really, your list has to know what it is a list of so you
define a sort procedure
which compares 2 items (passed as untyped pointers
e.g this is one I wrote
function ItemsCompare(Item1, Item2: Pointer): Integer;
var
MenuItem1, MenuItem2: TDBMenuItem;
begin
Result := 0;
MenuItem1 := Item1;
MenuItem2 := Item2;
if MenuItem1.Level = MenuItem2.Level then
begin
if MenuItem1.Position = MenuItem2.Position then Result := 0;
if MenuItem1.Position < MenuItem2.Position then Result := -1;
if MenuItem1.Position > MenuItem2.Position then Result := 1;
Exit;
end;
if MenuItem1.Level < MenuItem2.Level then Result := -1;
if MenuItem1.Level > MenuItem2.Level then Result := 1;
end;
then you call the sort method with the proc as parameter
Mylist.Sort(ItemsCompare);
easy once you start writing OO i.e define the items on your list as a class
regards
neven
----- Original Message -----
From: Coulter, Jeremy <[EMAIL PROTECTED]>
To: Multiple recipients of list delphi <[EMAIL PROTECTED]>
Sent: Wednesday, 17 November 1999 10:20
Subject: RE: [DUG]: Sorting
> I did look a this is in the begining, BUT I found it confusing how to
> implement a sort.
> I looked at a few excamples, but none really made any sence.
>
> Cheers,
>
> Jeremy Coulter
> Application Developer
>
> Application Development Centre
> Compaq Computer New Zealand Ltd.
>
> Phone: 64 3 371 5724
> Fax: 64 3 371 5724
> Mobile: 64 0212533214
> E-mail: [EMAIL PROTECTED]
> Personal Email: [EMAIL PROTECTED]
>
>
>
> -----Original Message-----
> From: Neven MacEwan [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, November 17, 1999 10:10 AM
> To: Multiple recipients of list delphi
> Subject: Re: [DUG]: Sorting
>
>
> Jeremy
>
> Use a TList and implement a sort on it .... see the Sort method of Tlist
>
> Regards
> Neven
>
>
> ----- Original Message -----
> From: Jeremy Coulter <[EMAIL PROTECTED]>
> To: Multiple recipients of list delphi <[EMAIL PROTECTED]>
> Sent: Wednesday, 17 November 1999 08:28
> Subject: [DUG]: Sorting
>
>
> > Hi all.
> >
> > I have been working on a wee logfile analyzer component for myself.
> > Basically it loads a CSV file(like one generated bt IIS) into memory and
> > then analyzes the entries.
> > I.e. in the case of the CSV file from IIS which i am using for
developing,
> > it calculates how many times an IP adress appears, and calculates how
many
> > bytes were sent to that IP address, i.e. the result :=
> 192.168.0.1,20,10000
> > (ip address, number of times it appears, how man bytes)
> >
> > Anyway, one of the things I do is load the file into a TStringList, and
> then
> > I sort it so i get all the, in this case, IP address grouped togeither,
> > which makes it easier to calculate everything, as all the relevient data
> is
> > all togeiter.
> >
> > BUT, I have a 7322 line file, and if I sort it, the process of zipping
> > through the file takes 22 seconds, remove the sorting, 0.461 seconds
!!!!
> >
> > SO, is there a faster way of sorting ?
> > Should I use an inmemory table...and if so, can I sort the fields
etc.....
> >
> > Any suggestions,
> >
> > Cheers, Jeremy Coulter
> >
> >
>
> --------------------------------------------------------------------------
> -
> > New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
> > Website: http://www.delphi.org.nz
> >
>
> --------------------------------------------------------------------------
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> New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
> Website: http://www.delphi.org.nz
> --------------------------------------------------------------------------
-
> New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
> Website: http://www.delphi.org.nz
>
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Website: http://www.delphi.org.nz
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Website: http://www.delphi.org.nz
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