График и отображаемый в память файл

unit
 MapGForm;

interface


uses

  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, SyncObjs, TeEngine, Series, ExtCtrls, TeeProcs, Chart, Grids,
  ComCtrls;

type

  TForm1 = class
(TForm)
    Timer1: TTimer;
    Chart1: TChart;
    Series1: TBarSeries;
    procedure
 FormCreate(Sender: TObject);
    procedure
 FormDestroy(Sender: TObject);
    procedure
 Timer1Timer(Sender: TObject);
  private

    hMapFile: THandle;
    MapFilePointer: Pointer;
  public

    procedure
 WmUser(var
 Msg: TMessage); message
 wm_user;
  end
;

var

  Form1: TForm1;

implementation


{$R *.DFM}

procedure
 TForm1.FormCreate(Sender: TObject);
var

  Address: Pointer;
  X, Y, Total: Integer;
begin

  hMapFile := CreateFileMapping(
    $FFFFFFFF, // file handle ... or memory
    nil
, // security
    Page_ReadWrite, // access rights
    0, // high memory size
    10000, // low memory size
    'DdhMappedFileGraph'); // mapped file name
  if
 hMapFile <> 0 then

    MapFilePointer := MapViewOfFile(
      hMapFile, // handle returned above
      File_Map_All_Access, // access rights
      0, 0, 0) // access the entire mapped file
  else

    ShowMessage('hMapFile = 0');
  if
 MapFilePointer = nil
 then

    ShowMessage('MapFilePointer = nil')
  else

  begin

    // add window to area
    Address := pChar(MapFilePointer) + 400;
    while
 PInteger(Address)^ <> 0 do

      Address := pChar(Address) + 4;
    PInteger(Address)^ := Handle;
  end
;
  // start up chart
  Chart1.Series[0].Clear;
  for
 X := 0 to
 9 do

  begin

    Total := 0;
    for
 Y := 0 to
 9 do

    begin

      Address := pChar(MapFilePointer) + (X + Y * 10) * 4;
      Inc(Total, PInteger(Address)^);
    end
;
    Chart1.Series[0].AddY(
      Total, IntToStr(X + 1), clRed);
  end
;
end
;

procedure
 TForm1.FormDestroy(Sender: TObject);
begin

  UnMapViewOfFile(MapFilePointer);
  CloseHandle(hMapFile);
end
;

procedure
 TForm1.WmUser(var
 Msg: TMessage);
var

  X, Y, Total: Integer;
  Address: Pointer;
begin

  // copy all the data to the graph
  for
 X := 0 to
 9 do

  begin

    Total := 0;
    for
 Y := 0 to
 9 do

    begin

      Address := pChar(MapFilePointer) + (X + Y * 10) * 4;
      Inc(Total, PInteger(Address)^);
    end
;
    Chart1.Series[0].YValue[X] := Total;
  end
;
end
;

procedure
 TForm1.Timer1Timer(Sender: TObject);
var

  X, Y: Integer;
  Address: Pointer;
begin

  X := Random(10);
  Y := Random(10);
  Address := pChar(MapFilePointer) + (X + Y * 10) * 4;
  PInteger(Address)^ := PInteger(Address)^ + Random(10);
  Address := pChar(MapFilePointer) + 400;
  while
 PInteger(Address)^ <> 0 do

  begin

    PostMessage(PInteger(Address)^, wm_user, 0, 0);
    Address := pChar(Address) + 4;
  end
;
end
;

initialization

  Randomize;
end
.

Другое по теме:

• Как скопировать все файлы вместе с подкаталогами
• Копирование файлов
• Удалить файл в корзину? Запросто!