Работа с коллекциями - сохранение и загрузка

Code:

unit PersForm;

interface

uses

Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,

Buttons, StdCtrls, ExtCtrls;

type

TForm1 = class(TForm)

   Panel1: TPanel;

   Label1: TLabel;

   Edit1: TEdit;

   SpeedButtonLoad: TSpeedButton;

   SpeedButtonSave: TSpeedButton;

   OpenDialog1: TOpenDialog;

   SaveDialog1: TSaveDialog;

   procedure FormCreate(Sender: TObject);

   procedure SpeedButtonSaveClick(Sender: TObject);

   procedure SpeedButtonLoadClick(Sender: TObject);

   procedure FormMouseDown(Sender: TObject; Button: TMouseButton;

     Shift: TShiftState; X, Y: Integer);

   procedure FormDestroy(Sender: TObject);

   procedure FormPaint(Sender: TObject);

private

   PtList: TCollection;

end;

var

Form1: TForm1;

implementation

{$R *.DFM}

uses

DelphiPt;

procedure TForm1.FormCreate(Sender: TObject);

begin

PtList := TCollection.Create (TDDHPoint);

end;

procedure TForm1.SpeedButtonSaveClick(Sender: TObject);

var

Str1: TFileStream;

Wrap: TWrapper;

begin

if SaveDialog1.Execute then

begin

   Str1 := TFileStream.Create (SaveDialog1.FileName,

     fmOpenWrite or fmCreate);

   try

     Wrap := TWrapper.Create (self);

     try

       Wrap.MyColl.Assign (ptList);

       Str1.WriteComponent (Wrap);

     finally

       Wrap.Free;

     end;

   finally

     Str1.Free;

   end;

end;

end;

procedure TForm1.SpeedButtonLoadClick(Sender: TObject);

var

Str1: TFileStream;

Wrap: TWrapper;

begin

if OpenDialog1.Execute then

begin

   Str1 := TFileStream.Create (

     OpenDialog1.Filename, fmOpenRead);

   try

     Wrap := TWrapper.Create (self);

     try

       Wrap := Str1.ReadComponent (Wrap) as TWrapper;

       ptList.Assign (Wrap.MyColl);

     finally

       Wrap.Free;

     end;

   finally

     Str1.Free;

     Invalidate;

     Edit1.Text := 'Point ' + IntToStr (PtList.Count + 1);

   end;

end;

end;

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;

Shift: TShiftState; X, Y: Integer);

var

Pt: TDDHPoint;

begin

Pt := PtList.Add as TDDHPoint;

Pt.X := X;

Pt.Y := Y;

Pt.Text := Edit1.Text;

Edit1.Text := 'Point ' + IntToStr (PtList.Count + 1);

Invalidate;

end;

procedure TForm1.FormDestroy(Sender: TObject);

begin

// empty and destroy the list

PtList.Clear;

PtList.Free;

end;

procedure TForm1.FormPaint(Sender: TObject);

var

I: Integer;

begin

for I := 0 to PtList.Count - 1 do

   TDDHPoint (PtList.Items [I]).Paint (Canvas);

end;

end.