變態的作法，爲了讓DateTimePicker在選擇日期後可以得焦點

        protected override void OnCloseUp(EventArgs eventargs)
        {
            if (this.Text.Equals(" "))
            {
                OnValueChanged(eventargs);
            }

            //SendKeys.Send("{RIGHT}");

            Cursor cur = this.Cursor;
            Point p = Cursor.Position;

            //Point yearPoint = this.PointToScreen(new Point(this.Left + 5, this.Top + 5));
            int x = this.FindForm().Left + this.FindForm().ClientRectangle.X + this.Left + 20;
            int y = this.FindForm().Top + this.FindForm().ClientRectangle.Y + this.Top + 5 +
                this.FindForm().Height – this.FindForm().ClientRectangle.Height;
            Point yearPoint = new Point(x, y);
            this.Cursor = Cursors.No;
            Cursor.Position = yearPoint;

            long lparam = MakeDWord(5, 5);

            SendMessage(this.Handle, 0x0201, (IntPtr)1, (IntPtr)lparam);
            SendMessage(this.Handle, 0x0202, (IntPtr)1, (IntPtr)lparam);
            Cursor.Position = p;
            this.Cursor = cur;
           
            base.OnCloseUp(eventargs);
        }

        private long MakeDWord(int wLo, int wHi)
        {
            long ret = 0;

            ret = (wHi * 0x10000) | (wLo & 0xffff);

            return ret;
        }