关于记录 ,一句话问题 ( 积分: 50 )

O

offline

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-11

• #1

请教包含动态数组的记录,应该怎么释放?
如:
TMyRecord=record
member1:integer;
member2:string;
aArray:array of integer;
end;
var
aMyRecord:TMyRecord;

释放aMyRecord时需要setLength(aMyRecord.aArray,0)吗?
谢谢!

 

O

offline

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-11

• #2

请教包含动态数组的记录,应该怎么释放?
如:
TMyRecord=record
member1:integer;
member2:string;
aArray:array of integer;
end;
var
aMyRecord:TMyRecord;

释放aMyRecord时需要setLength(aMyRecord.aArray,0)吗?
谢谢!

 

A

aimeoo

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-19

• #3

aArray:=nil;

 

O

offline

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-12

• #4

假如在函数里边,
如
procedure pro1;
var aMyRecord:TMyRecord;
begin
{
do something...
}
end;
这里的aMyRecord 不需要nil吧?

 

A

aimeoo

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GUEST, unregistred user!

• 2005-08-12

• #5

看你的动态数组怎么用了，如果要重复执行你的“函数”那就在动态数组初始化前把它nil掉～

 

O

offline

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-12

• #6

record类型不能nil吧?
提示类型不匹配

 

A

AIJunWei1225

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-12

• #7

记录不能释放。只能释放数组。
unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls;

type
TMyRecord=record
member1:integer;
member2:string;
aArray:array of integer;
end;

TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var Arr: TMyRecord;
begin
arr.member1:=20;
arr.member2:='20str';
setlength(arr.aArray,1);
arr.aArray[0]:=90;
showmessage(inttostr(arr.aArray[0]));
Initialize(arr.aArray);
If Arr.aArray<> nil then showmessage('OK');
end;

end.

 

X

xeen

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-12

• #8

动态数组是内存自管理类型，一般来说不用主动释放。

 

O

offline

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-12

• #9

动态数组肯定要释放得,系统不自动管理

 

J

Jonson_sunshine

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-08-12

• #10

如真要自己管理，可用指针
type
MyPointer = ^TMyRecord;
TMyRecord=record
member1:integer;
member2:string;
aArray:array of integer;
end;

声明：
procedure pro1;
var
APointer :MyPointer

aMyRecord:TMyRecord;
begin
new(APointer)

aMyRecord.member1 :=10;
APointer :=@aMyRecord;
showmessage(inttostr(APointer.member1));
APointer :=nil;
.....//剩下代码不能再访问 APointer;
end;

 

J

Jonson_sunshine

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GUEST, unregistred user!

• 2005-08-12

• #11

Delphi本身有个TList类，管理指针数组的，可以参考其中的单元代码定义你自己的类型

 

H

harryduan

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-09-01

• #12

我不同意offline的说法
在delphi中动态数组和字符串一样都是引用记数的，当引用为0时自动释放。
但是动态数据不支持copy-on-write技术

另外也可以手动释放，有两中方法，finalize过程或将动态数组名= nil

 

O

offline

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2005-10-16

• #13

那还是要释放啊，让他长度等于0还不是要设setLength(dynArray,0)吗呵呵