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{
Copyright © 1999 by Delphi 5 Developer's Guide - Xavier Pacheco and Steve Teixeira
}

unit
 MainFrm;

interface


uses

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

const

  DString = 'Delphi 5 YES!';
  DString2 = 'Delphi 5 Rocks!';

type


  TMainForm = class
(TForm)
    mmMain: TMainMenu;
    mmiText: TMenuItem;
    mmiTextRect: TMenuItem;
    mmiTextSize: TMenuItem;
    mmiDrawTextCenter: TMenuItem;
    mmiDrawTextRight: TMenuItem;
    mmiDrawTextLeft: TMenuItem;
    procedure
 mmiTextRectClick(Sender: TObject);
    procedure
 mmiTextSizeClick(Sender: TObject);
    procedure
 mmiDrawTextCenterClick(Sender: TObject);
    procedure
 mmiDrawTextRightClick(Sender: TObject);
    procedure
 mmiDrawTextLeftClick(Sender: TObject);
  public

    procedure
 ClearCanvas;
  end
;

var

  MainForm: TMainForm;

implementation


{$R *.DFM}

procedure
 TMainForm.ClearCanvas;
begin

  with
 Canvas do

  begin

    Brush.Style := bsSolid;
    Brush.Color := clWhite;
    FillRect(ClipRect);
  end
;
end
;

procedure
 TMainForm.mmiTextRectClick(Sender: TObject);
var

  R: TRect;
  TWidth, THeight: integer;
begin

  ClearCanvas;
  Canvas.Font.Size := 18;
  // Calculate the width/height of the text string
  TWidth := Canvas.TextWidth(DString);
  THeight := Canvas.TextHeight(DString);

  { Initialize a TRect structure. The height of this rectangle will
    be 1/2 the height of the text string height. This is to
    illustrate clipping the text by the rectangle drawn }
  R := Rect(1, THeight div
 2, TWidth + 1, THeight + (THeight div
 2));
  // Draw a rectangle based on the text sizes
  Canvas.Rectangle(R.Left - 1, R.Top - 1, R.Right + 1, R.Bottom + 1);
  // Draw the Text within the rectangle
  Canvas.TextRect(R, 0, 0, DString);
end
;

procedure
 TMainForm.mmiTextSizeClick(Sender: TObject);
begin

  ClearCanvas;
  with
 Canvas do

  begin

    Font.Size := 18;
    TextOut(10, 10, DString);
    TextOut(50, 50, 'TextWidth = ' + IntToStr(TextWidth(DString)));
    TextOut(100, 100, 'TextHeight = ' + IntToStr(TextHeight(DString)));
  end
;
end
;

procedure
 TMainForm.mmiDrawTextCenterClick(Sender: TObject);
var

  R: TRect;
begin

  ClearCanvas;
  Canvas.Font.Size := 10;
  R := Rect(10, 10, 80, 100);
  // Draw a rectangle to surround the TRect boundaries by 2 pixels }
  Canvas.Rectangle(R.Left - 2, R.Top - 2, R.Right + 2, R.Bottom + 2);
  // Draw text centered by specifying the dt_Center option
  DrawText(Canvas.Handle, PChar(DString2), -1, R, dt_WordBreak or
 dt_Center);
end
;

procedure
 TMainForm.mmiDrawTextRightClick(Sender: TObject);
var

  R: TRect;
begin

  ClearCanvas;
  Canvas.Font.Size := 10;
  R := Rect(10, 10, 80, 100);
  // Draw a rectangle to surround the TRect boundaries by 2 pixels
  Canvas.Rectangle(R.Left - 2, R.Top - 2, R.Right + 2, R.Bottom + 2);
  // Draw text right-aligned by specifying the dt_Right option
  DrawText(Canvas.Handle, PChar(DString2), -1, R, dt_WordBreak or
 dt_Right);
end
;

procedure
 TMainForm.mmiDrawTextLeftClick(Sender: TObject);
var

  R: TRect;
begin

  ClearCanvas;
  Canvas.Font.Size := 10;
  R := Rect(10, 10, 80, 100);
  // Draw a rectangle to surround the TRect boudries by 2 pixels
  Canvas.Rectangle(R.Left - 2, R.Top - 2, R.Right + 2, R.Bottom + 2);
  // Draw text left-aligned by specifying the dt_Left option
  DrawText(Canvas.Handle, PChar(DString2), -1, R, dt_WordBreak or
 dt_Left);
end
;

end
.

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