本例效果图:
代码文件:
unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, DIB, StdCtrls; type TForm1 = class(TForm) DXPaintBox1: TDXPaintBox; Button1: TButton; Button2: TButton; procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); procedure FormCreate(Sender: TObject); procedure FormDestroy(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} var dib: TDIB; procedure TForm1.Button1Click(Sender: TObject); begin DXPaintBox1.DIB.Fill(clGray); DXPaintBox1.DIB.DrawTo(dib, dib.Width div 3, dib.Height div 3, dib.Width, dib.Height, 0, 0); DXPaintBox1.Repaint; end; procedure TForm1.Button2Click(Sender: TObject); begin DXPaintBox1.DIB.Fill(clGray); DXPaintBox1.DIB.DrawTo(dib, 0, 0, dib.Width, dib.Height, dib.Width div 3, dib.Height div 3); DXPaintBox1.Repaint; end; procedure TForm1.FormCreate(Sender: TObject); const ImgPath1 = 'C:\Temp\DX.jpg'; begin dib := TDIB.Create; dib.LoadFromFile(ImgPath1); DXPaintBox1.DIB.Assign(dib); DXPaintBox1.Width := dib.Width; DXPaintBox1.Height := dib.Height; DXPaintBox1.Repaint; end; procedure TForm1.FormDestroy(Sender: TObject); begin dib.Free; end; end.
窗体文件:
object Form1: TForm1 Left = 0 Top = 0 Caption = 'Form1' ClientHeight = 142 ClientWidth = 226 Color = clBtnFace Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -11 Font.Name = 'Tahoma' Font.Style = [] OldCreateOrder = False OnCreate = FormCreate OnDestroy = FormDestroy PixelsPerInch = 96 TextHeight = 13 object DXPaintBox1: TDXPaintBox Left = 8 Top = 8 Width = 81 Height = 73 AutoStretch = False Center = False KeepAspect = False Stretch = False ViewWidth = 0 ViewHeight = 0 end object Button1: TButton Left = 143 Top = 78 Width = 75 Height = 25 Caption = 'Button1' TabOrder = 0 OnClick = Button1Click end object Button2: TButton Left = 143 Top = 109 Width = 75 Height = 25 Caption = 'Button2' TabOrder = 1 OnClick = Button2Click end end