unit printpreview;
interface
uses
 Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
 StdCtrls, ExtCtrls, ComCtrls;
type
 TForm1 = class(TForm)
  Panel1: TPanel;
  Panel2: TPanel;
  PreviewPaintbox: TPaintBox;
  Label1: TLabel;
  Label2: TLabel;
  LeftMarginEdit: TEdit;
  MarginEdit: TEdit;
  Label3: TLabel;
  Label4: TLabel;
  RightMarginEdit: TEdit;
  Label5: TLabel;
  BottomMarginEdit: TEdit;
  ApplyMarginsButton: TButton;
  OrientationRGroup: TRadioGroup;
  Label6: TLabel;
  ZoomEdit: TEdit;
  ZoomUpDown: TUpDown;
  procedure LeftMarginEditKeyPress(Sender: TObject; var Key: Char);
  procedure FormCreate(Sender: TObject);
  procedure PreviewPaintboxPaint(Sender: TObject);
  procedure ApplyMarginsButtonClick(Sender: TObject);
 private
  { Private declarations }
  PreviewText: String;
 public
  { Public declarations }
 end;
var
 Form1: TForm1;
implementation
uses printers;
{$R *.DFM}
procedure TForm1.LeftMarginEditKeyPress(Sender: TObject; var Key: Char);
begin
 If not (Key in ['0'..'9',#9,DecimalSeparator]) Then
  Key := #0;
end;
procedure TForm1.FormCreate(Sender: TObject);
var
 S: String;
 procedure loadpreviewtext;
 var
  sl: TStringlist;
 begin
  sl:= Tstringlist.Create;
  try
  sl.Loadfromfile( Extractfilepath( application.exename )+'printpreview.pas');
  PreviewText := sl.Text;
  finally
  sl.free
  end;
 end;
begin
 // Initialize the margin edits with a margin of 0.75 inch
 S:= FormatFloat('0.00',0.75);
 LeftMarginEdit.Text := S;
 MarginEdit.Text := S;
 RightMarginEdit.Text := S;
 BottomMarginEdit.Text := S;
 // Initialize the orientation radio group
 If Printer.Orientation = poPortrait Then
  OrientationRGroup.ItemIndex := 0
 Else
  OrientationRGroup.ItemIndex := 1;
 // load test text for display
 LoadPreviewtext;
end;
procedure TForm1.PreviewPaintboxPaint(Sender: TObject);
var
 pagewidth, pageheight: Double; // printer page dimension in inch
 printerResX, printerResY: Integer; // printer resolution in dots/inch
 minmarginX, minmarginY: Double; // nonprintable margin in inch
 outputarea: TRect; // print area in 1/1000 inches
 scale: Double; // conversion factor, pixels per 1/1000 inch
 procedure InitPrintSettings;
  function GetMargin( S: String; inX: Boolean ):Double;
  begin
  Result := StrToFloat(S);
  if InX then begin
  if Result < minmarginX then
  Result := minmarginX;
  end
  else begin
  if Result < minmarginY then
  Result := minmarginY;
  end;
  end;
 begin
  printerResX := GetDeviceCaps( printer.handle, LOGPIXELSX );
  printerResY := GetDeviceCaps( printer.handle, LOGPIXELSY );
  pagewidth := GetDeviceCaps( printer.handle, PHYSICALWIDTH ) / printerResX;
  pageheight := GetDeviceCaps( printer.handle, PHYSICALHEIGHT) / printerResY;
  minmarginX := GetDeviceCaps( printer.handle, PHYSICALOFFSETX)/ printerResX;
  minmarginY := GetDeviceCaps( printer.handle, PHYSICALOFFSETY)/ printerResY;
  outputarea.Left := Round( GetMargin( LeftMarginEdit.Text, true ) * 1000);
  outputarea. := Round( GetMargin( MarginEdit.Text, false ) * 1000);
  outputarea.Right := Round(( pagewidth -
  GetMargin( RightMarginEdit.Text, true )) * 1000);
  outputarea.Bottom := Round(( pageheight -
  GetMargin( BottomMarginEdit.Text, false ))
  * 1000);
 end; { InitPrintSettings }