效果图如下：
实现平台：xp xe2，其中以上功能的实现，核心主要是参考了万一老师的资料，连接：http://www.cnblogs.com/del/archive/2011/05/12/2044112.html
完整代码如下：
unit Unit1; interface uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.ComCtrls, Vcl.ImgList, RzButton,
Vcl.ExtCtrls, RzPanel, Vcl.StdCtrls; type
TForm1 = class(TForm)
ImageList1: TImageList;
RzToolbar1: TRzToolbar;
RzToolButton1: TRzToolButton;
MonthCalendar1: TMonthCalendar;
Memo1: TMemo;
procedure FormCreate(Sender: TObject);
procedure RzToolButton1Click(Sender: TObject);
procedure MonthCalendar1Click(Sender: TObject);
procedure MonthCalendar1GetMonthBoldInfo(Sender: TObject; Month,
Year: Cardinal; var MonthBoldInfo: Cardinal);
private
{ Private declarations }
procedure MouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X: Integer; Y: Integer);
procedure MouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X: Integer; Y: Integer);
public
{ Public declarations }
end; var
Form1: TForm1;
yy,mm,dd: string; //存年月日
y1,m1,d1: Word; //从DecordDate函数解析年月日，然后传值给yy,mm,dd implementation {$R *.dfm} procedure TForm1.FormCreate(Sender: TObject);
begin
DecodeDate(MonthCalendar1.Date,y1,m1,d1);
yy := IntToStr(y1);
mm := IntToStr(m1);
dd := IntToStr(d1);
MonthCalendar1.Visible := False;
RzToolButton1.Caption := DateToStr(MonthCalendar1.Date);
//TFrom和TMonthCalendar都是由TControl的派生来的，TMonthCalendar通过TForm间接继承OnMouseUp、OnMouseDown属性
TForm1(MonthCalendar1).OnMouseUp := MouseUp;
TForm1(MonthCalendar1).OnMouseDown := MouseDown;
end; procedure TForm1.RzToolButton1Click(Sender: TObject);
begin
MonthCalendar1.Visible := not MonthCalendar1.Visible;
if MonthCalendar1.Visible then
begin
MonthCalendar1.BringToFront;
Memo1.Align := alRight;
Memo1.Width := 100;
end else Memo1.Align := alClient;
end; procedure TForm1.MonthCalendar1Click(Sender: TObject);
begin
RzToolButton1.Caption := DateToStr(MonthCalendar1.Date);
end; procedure TForm1.MonthCalendar1GetMonthBoldInfo(Sender: TObject; Month,
Year: Cardinal; var MonthBoldInfo: Cardinal);
begin
yy := Format('%u',[Year]);
RzToolButton1.Caption := yy + '-' + mm + '-' + dd;
end; procedure TForm1.MouseUp(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
DecodeDate(MonthCalendar1.Date,y1,m1,d1);
dd := IntToStr(d1);
if Y >= 48 then //测量所得，单击日历横线下面的区域日历隐藏
begin
MonthCalendar1.Visible := False;
Memo1.Align := alClient;
end;
end; procedure TForm1.MouseDown(Sender: TObject; Button: TMouseButton; Shift: TShiftState; X: Integer; Y: Integer);
begin
DecodeDate(MonthCalendar1.Date,y1,m1,d1);
mm := IntToStr(m1);
//dd := IntToStr(d1);
RzToolButton1.Caption := DateToStr(MonthCalendar1.Date);
end; end.