BitBlt( DestDC: HDC; {目标 DC} X, Y, Width, Height: Integer; {目标位置与大小} SrcDC: HDC; {源 DC} XSrc, YSrc: Integer; {源起始位置} Rop: DWORD {光栅操作码, 也就是源像素与目标像素的混合方式} ): BOOL; //可以使用光栅操作码的函数还有: PatBlt、StretchBlt、StretchDIBits本例效果图:
![](https://www.cnblogs.com/images/cnblogs_com/del/138617/o_86251.gif)
代码文件:
unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls, ExtCtrls; type TForm1 = class(TForm) Panel1: TPanel; Panel2: TPanel; Panel3: TPanel; ListBox1: TListBox; procedure FormCreate(Sender: TObject); procedure FormDestroy(Sender: TObject); procedure FormPaint(Sender: TObject); procedure ListBox1Click(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} var bit1,bit2: TBitmap; cvs1,cvs2,cvs3: TCanvas; procedure TForm1.FormCreate(Sender: TObject); begin with ListBox1.Items do begin Add('SRCCOPY '); Add('SRCPAINT '); Add('SRCAND '); Add('SRCINVERT '); Add('SRCERASE '); Add('NOTSRCCOPY '); Add('NOTSRCERASE'); Add('MERGECOPY '); Add('MERGEPAINT '); Add('PATCOPY '); Add('PATPAINT '); Add('PATINVERT '); Add('DSTINVERT '); Add('BLACKNESS '); Add('WHITENESS '); end; Panel1.Caption := ''; Panel2.Caption := ''; Panel3.Caption := ''; bit1 := TBitmap.Create; bit1.Width := Panel1.ClientWidth; bit1.Height := Panel1.ClientHeight; bit2 := TBitmap.Create; bit2.Width := Panel2.ClientWidth; bit2.Height := Panel2.ClientHeight; cvs1 := TCanvas.Create; cvs2 := TCanvas.Create; cvs3 := TCanvas.Create; cvs1.Handle := GetDC(Panel1.Handle); cvs2.Handle := GetDC(Panel2.Handle); cvs3.Handle := GetDC(Panel3.Handle); end; procedure TForm1.FormDestroy(Sender: TObject); begin bit1.Free; bit2.Free; cvs1.Free; cvs2.Free; cvs3.Free; end; procedure TForm1.FormPaint(Sender: TObject); const ColorArr: array[0..5] of TColor = (clRed, clGreen, clBlue, clYellow, clFuchsia, clPurple); var wi,hi: Integer; I: Integer; begin wi := bit1.Width div 4; hi := bit1.Height div 4; bit1.Canvas.Pen.Width := 10; for I := 1 to 3 do begin bit1.Canvas.Pen.Color := ColorArr[i-1]; bit1.Canvas.MoveTo(wi*i, 0); bit1.Canvas.LineTo(wi*i, bit1.Height); bit1.Canvas.Pen.Color := ColorArr[i+2]; bit1.Canvas.MoveTo(0, hi*i); bit1.Canvas.LineTo(bit1.Width, hi*i); end; bit2.Canvas.Pen.Width := 15; bit2.Canvas.Ellipse(15, 15, bit2.Width-15, bit2.Height-15); cvs1.Draw(0, 0, bit1); cvs2.Draw(0, 0, bit2); end; procedure TForm1.ListBox1Click(Sender: TObject); var Rop: Cardinal; begin Repaint; Rop := SRCCOPY; case ListBox1.ItemIndex of 0 : Rop := SRCCOPY ; 1 : Rop := SRCPAINT ; 2 : Rop := SRCAND ; 3 : Rop := SRCINVERT ; 4 : Rop := SRCERASE ; 5 : Rop := NOTSRCCOPY ; 6 : Rop := NOTSRCERASE; 7 : Rop := MERGECOPY ; 8 : Rop := MERGEPAINT ; 9 : Rop := PATCOPY ; 10: Rop := PATPAINT ; 11: Rop := PATINVERT ; 12: Rop := DSTINVERT ; 13: Rop := BLACKNESS ; 14: Rop := WHITENESS ; end; cvs3.Draw(0, 0, bit1); BitBlt(cvs3.Handle, (bit1.Width - bit2.Width) div 2, (bit1.Height - bit2.Height) div 2, bit2.Width, bit2.Height, bit2.Canvas.Handle, 0, 0, Rop); end; end.窗体文件:
object Form1: TForm1 Left = 0 Top = 0 Caption = 'Form1' ClientHeight = 300 ClientWidth = 319 Color = clBtnFace Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -11 Font.Name = 'Tahoma' Font.Style = [] OldCreateOrder = False Position = poDesktopCenter OnCreate = FormCreate OnDestroy = FormDestroy OnPaint = FormPaint PixelsPerInch = 96 TextHeight = 13 object Panel1: TPanel Left = 8 Top = 8 Width = 180 Height = 140 Caption = 'Panel1' TabOrder = 0 end object Panel2: TPanel Left = 194 Top = 8 Width = 119 Height = 105 Caption = 'Panel2' TabOrder = 1 end object Panel3: TPanel Left = 8 Top = 154 Width = 180 Height = 140 Caption = 'Panel3' TabOrder = 2 end object ListBox1: TListBox Left = 194 Top = 119 Width = 119 Height = 176 ItemHeight = 13 TabOrder = 3 OnClick = ListBox1Click end end