asked on

dynamic array of records in dynamic array of records!!

Hey all,

I have a couple of records as follows :

type
WEAPON = record
size : byte;
posX : double;
posY : double;
posZ : double;
rotX : double;
rotY : double;
rotZ : double;
end;

type
DATA = record
LowestX : double;
LowestY : double;
HighestX : double;
HighestY : double;
weight : double;
braking : double;
power : double;
hitpoints : integer;
cost : integer;
name : string;
path : string;
WeaponsNumber : byte;
Weapons : array of WEAPON; //<---- right here!
end;

As u see, the DATA record has an array of WEAPON at the bottom.... ( as shown)

now i have a global dynamic array of DATA which works fine,

Tanks : array of DATA;

and i can call stuff like

SetLength(Tanks, 100);
Tanks[0].weight = 1000;

but when i call SetLength on the WEAPONS record within the DATA one, an access violation occurs...
i.e.
SetLength(Tanks[0].Weapons, 100); //Access violation!!!

Please help!!!

Regards,
-Rob-

ASKER CERTIFIED SOLUTION

jconde

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jconde

BTW, even though it would slightly add complexity to your code, I would suggest you use a TList for this instead of a dynamic array.

geobul

Hi,

No access violation occurs in my Delphi 5. Everything is just fine:

var
Form1: TForm1;
Tanks : array of DATA;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
begin
SetLength(Tanks, 100);
Tanks[0].weight := 1000;
SetLength(Tanks[0].Weapons, 100);
Tanks[0].Weapons[0].PosX := 100.25;
ShowMessage(FloatToStr(Tanks[0].Weapons[0].PosX));
end;

Regards, Geo

ZhaawZ

btw, you could use length(tanks[n].weapons) instead of tanks[n].weaponnumber ;)

Excalibur81

ASKER

Ahhh i see now, it was a logic mistake :)

Hmm, so since there was actually no problem, how do points work??

Also.....

"BTW, even though it would slightly add complexity to your code, I would suggest you use a TList for this instead of a dynamic array. "
Unfortunatly, im saving the data in a file which will be read later on by a program in C++, and needs to be in this fairly specific format.... thanks anyways :)

"btw, you could use length(tanks[n].weapons) instead of tanks[n].weaponnumber ;) "
Yes i had seen that, but for now im just using this for debugging purposes, but thanks also :)

jconde

I beleive you should split the points between geobul and myself. geobul, what do you suggest ?

geobul

jconde should get the points. I just confirmed that for D5.

Excalibur81

ASKER

Thanks guys :)

Soz, i meant to split the points, but ive never done before, and i thought it was inside the "Accept Answer" path....

but i guess geobul didnt want them anyways :D

Thanks!!!