unit1.pas

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unit Unit1;

interface

uses
  Windows, Buttons, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;

type
  TForm1 = class(TForm)
    procedure FormResize(Sender: TObject);
  private
    { Private declarations }
    CaptionBtn:TRect;
    procedure DrawCaptButton;
    procedure WMNCPaint(var Msg:TWMNCPaint);message WM_NCPaint;
    procedure WMNCActivate(var Msg:TWMNCActivate);message WM_NCActivate;
    procedure WMSetText(var Msg:TWMSetText);message WM_SetText;
    procedure WMNCHitTest(var Msg:TWMNCHitTest);message WM_NCHittest;
    procedure WMNCLButtonDown(var Msg:TWMNCLButtonDown);message WM_NCLButtonDown;
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

const
  htCaptionBtn=htSizeLast+1;

{$R *.DFM}

procedure TForm1.DrawCaptButton;
var
  xFrame,yFrame,xSize,ySize:Integer;
  R:TRect;
begin
  xFrame:=GetSystemMetrics(SM_CXFRAME);
  yFrame:=GetSystemMetrics(SM_CYFRAME);
  xSize:=GetSystemMetrics(SM_CXSIZE);
  ySize:=GetSystemMetrics(SM_CYSIZE);
  //按钮属性调整->>
  CaptionBtn:=Bounds(Width-xFrame-70-5*xSize+3,yFrame+1,xSize+20,ySize-3);
  Canvas.Handle:=GetWindowDC(Self.Handle);
  Canvas.Font.Name:='宋体';
  Canvas.Font.Color:=clBlack;
  Canvas.Pen.Color:=clYellow;
  Canvas.Brush.Color:=clBtnFace;
  try
    DrawButtonFace(Canvas,CaptionBtn,1,bsAutoDetect,False,False,False);
    R:=Bounds(Width-xFrame-70-5*xSize+3,yFrame+1,xSize+15,ySize-5);
    with CaptionBtn do
      Canvas.TextRect(R,R.Left+7,R.Top+4,'点击我');
  finally
    ReleaseDC(Self.Handle,Canvas.Handle);
    Canvas.Handle:=0;
  end;
end;

procedure TForm1.WMNCActivate(var Msg: TWMNCActivate);
begin
inherited;
  DrawCaptButton;
end;

procedure TForm1.WMNCHitTest(var Msg: TWMNCHitTest);
begin
inherited;
  with Msg do
    if PtInRect(CaptionBtn,Point(xPos-Left,yPos-Top)) then
    Result:=htCaptionBtn;
end;

procedure TForm1.WMNCLButtonDown(var Msg: TWMNCLButtonDown);
begin
inherited;
  if(Msg.HitTest=htCaptionBtn)then
    Showmessage('这是在特殊位置的按钮哦！');
end;

procedure TForm1.WMNCPaint(var Msg: TWMNCPaint);
begin
inherited;
  DrawCaptButton;
end;

procedure TForm1.WMSetText(var Msg: TWMSetText);
begin
inherited;
  DrawCaptButton;
end;

procedure TForm1.FormResize(Sender: TObject);
begin
  Perform(WM_NCACTIVATE,Word(Active),0);
end;

end.