Практическое руководство. Заключение элемента управления в оболочку ToolStripControlHost в Windows Forms

Статья
08/11/2011

Оболочка ToolStripControlHost предназначена для размещения произвольных элементов управления Windows Forms с помощью конструктора ToolStripControlHost либо путем расширения самой оболочки ToolStripControlHost. Она позволяет упростить создание программы-оболочки для элемента управления путем расширения ToolStripControlHost и реализации свойств и методов, открывающих доступ к часто используемым свойствам и методом элемента управления. Кроме того, на уровне ToolStripControlHost можно предоставить доступ к методам элемента управления.

Заключение элемента управления в оболочку ToolStripControlHost путем наследования

Создайте расширение класса ToolStripControlHost. Реализуйте конструктор по умолчанию, вызывающий конструктор базового класса и передающий ему требуемый элемент управления.

' Call the base constructor passing in a MonthCalendar instance.
Public Sub New() 
    MyBase.New(New MonthCalendar())

End Sub

        // Call the base constructor passing in a MonthCalendar instance.
        public ToolStripMonthCalendar() : base (new MonthCalendar()) { }

// Call the base constructor passing in a MonthCalendar instance.
ToolStripMonthCalendar() : ToolStripControlHost( gcnew MonthCalendar ) {}

Объявите свойство того же типа, что и заключаемый в оболочку элемент управления, а в методе доступа для свойства укажите Control в качестве возвращаемого типа элемента управления.

Public ReadOnly Property MonthCalendarControl() As MonthCalendar 
    Get
        Return CType(Control, MonthCalendar)
    End Get
End Property

        public MonthCalendar MonthCalendarControl
        {
            get
            {
                return Control as MonthCalendar;
            }
        }

property MonthCalendar^ MonthCalendarControl 
{
   MonthCalendar^ get()
   {
      return static_cast<MonthCalendar^>(Control);
   }
}

Обеспечьте доступ к часто используемым свойствам и методам заключаемого в оболочку элемента управления с помощью свойств и методов расширенного класса.

' Expose the MonthCalendar.FirstDayOfWeek as a property.
Public Property FirstDayOfWeek() As Day 
    Get
        Return MonthCalendarControl.FirstDayOfWeek
    End Get
    Set
        MonthCalendarControl.FirstDayOfWeek = value
    End Set
End Property

' Expose the AddBoldedDate method.
Public Sub AddBoldedDate(ByVal dateToBold As DateTime) 
    MonthCalendarControl.AddBoldedDate(dateToBold)

End Sub

        // Expose the MonthCalendar.FirstDayOfWeek as a property.
        public Day FirstDayOfWeek
        {
            get
            {
                return MonthCalendarControl.FirstDayOfWeek;
            }
            set { MonthCalendarControl.FirstDayOfWeek = value; }
        }

        // Expose the AddBoldedDate method.
        public void AddBoldedDate(DateTime dateToBold)
        {
            MonthCalendarControl.AddBoldedDate(dateToBold);
        }

property Day FirstDayOfWeek 
{
   // Expose the MonthCalendar.FirstDayOfWeek as a property.
   Day get()
   {
      return MonthCalendarControl->FirstDayOfWeek;
   }

   void set( Day value )
   {
      MonthCalendarControl->FirstDayOfWeek = value;
   }
}

// Expose the AddBoldedDate method.
void AddBoldedDate( DateTime dateToBold )
{
   MonthCalendarControl->AddBoldedDate( dateToBold );
}

При необходимости можно переопределить методы OnSubscribeControlEvents и OnUnsubscribeControlEvents и добавить события элемента управления, к которым требуется открыть доступ.

Protected Overrides Sub OnSubscribeControlEvents(ByVal c As Control) 

    ' Call the base so the base events are connected.
    MyBase.OnSubscribeControlEvents(c)

    ' Cast the control to a MonthCalendar control.
    Dim monthCalendarControl As MonthCalendar = _
        CType(c, MonthCalendar)

    ' Add the event.
    AddHandler monthCalendarControl.DateChanged, _
        AddressOf HandleDateChanged

End Sub

Protected Overrides Sub OnUnsubscribeControlEvents(ByVal c As Control)
    ' Call the base method so the basic events are unsubscribed.
    MyBase.OnUnsubscribeControlEvents(c)

    ' Cast the control to a MonthCalendar control.
    Dim monthCalendarControl As MonthCalendar = _
        CType(c, MonthCalendar)

    ' Remove the event.
    RemoveHandler monthCalendarControl.DateChanged, _
        AddressOf HandleDateChanged

End Sub

        protected override void OnSubscribeControlEvents(Control c)
        {
            // Call the base so the base events are connected.
            base.OnSubscribeControlEvents(c);

            // Cast the control to a MonthCalendar control.
            MonthCalendar monthCalendarControl = (MonthCalendar) c;

            // Add the event.
            monthCalendarControl.DateChanged +=
                new DateRangeEventHandler(OnDateChanged);
        }

        protected override void OnUnsubscribeControlEvents(Control c)
        {
            // Call the base method so the basic events are unsubscribed.
            base.OnUnsubscribeControlEvents(c);

            // Cast the control to a MonthCalendar control.
            MonthCalendar monthCalendarControl = (MonthCalendar) c;

            // Remove the event.
            monthCalendarControl.DateChanged -=
                new DateRangeEventHandler(OnDateChanged);
        }

void OnSubscribeControlEvents( System::Windows::Forms::Control^ c )
{
   // Call the base so the base events are connected.
   __super::OnSubscribeControlEvents( c );

   // Cast the control to a MonthCalendar control.
   MonthCalendar^ monthCalendarControl = (MonthCalendar^)c;

   // Add the event.
   monthCalendarControl->DateChanged += gcnew DateRangeEventHandler( this, &ToolStripMonthCalendar::HandleDateChanged );
}

void OnUnsubscribeControlEvents( System::Windows::Forms::Control^ c )
{

   // Call the base method so the basic events are unsubscribed.
   __super::OnUnsubscribeControlEvents( c );

   // Cast the control to a MonthCalendar control.
   MonthCalendar^ monthCalendarControl = (MonthCalendar^)c;

   // Remove the event.
   monthCalendarControl->DateChanged -= gcnew DateRangeEventHandler( this, &ToolStripMonthCalendar::HandleDateChanged );
}

Обеспечьте оболочку для событий, к которым необходимо открыть доступ.

    ' Declare the DateChanged event.
    Public Event DateChanged As DateRangeEventHandler

    ' Raise the DateChanged event.
    Private Sub HandleDateChanged(ByVal sender As Object, _
        ByVal e As DateRangeEventArgs)

        RaiseEvent DateChanged(Me, e)
    End Sub
End Class

        // Declare the DateChanged event.
        public event DateRangeEventHandler DateChanged;

        // Raise the DateChanged event.
        private void OnDateChanged(object sender, DateRangeEventArgs e)
        {
            if (DateChanged != null)
            {
                DateChanged(this, e);
            }
        }

// Declare the DateChanged event.
// Raise the DateChanged event.
void HandleDateChanged( Object^ sender, DateRangeEventArgs^ e )
{
   if ( DateChanged != nullptr )
   {
      DateChanged( this, e );
   }
}

Пример

'Declare a class that inherits from ToolStripControlHost.

Public Class ToolStripMonthCalendar
    Inherits ToolStripControlHost

    ' Call the base constructor passing in a MonthCalendar instance.
    Public Sub New() 
        MyBase.New(New MonthCalendar())

    End Sub

    Public ReadOnly Property MonthCalendarControl() As MonthCalendar 
        Get
            Return CType(Control, MonthCalendar)
        End Get
    End Property

    ' Expose the MonthCalendar.FirstDayOfWeek as a property.
    Public Property FirstDayOfWeek() As Day 
        Get
            Return MonthCalendarControl.FirstDayOfWeek
        End Get
        Set
            MonthCalendarControl.FirstDayOfWeek = value
        End Set
    End Property

    ' Expose the AddBoldedDate method.
    Public Sub AddBoldedDate(ByVal dateToBold As DateTime) 
        MonthCalendarControl.AddBoldedDate(dateToBold)

    End Sub

    ' Subscribe and unsubscribe the control events you wish to expose.
    Protected Overrides Sub OnSubscribeControlEvents(ByVal c As Control) 

        ' Call the base so the base events are connected.
        MyBase.OnSubscribeControlEvents(c)

        ' Cast the control to a MonthCalendar control.
        Dim monthCalendarControl As MonthCalendar = _
            CType(c, MonthCalendar)

        ' Add the event.
        AddHandler monthCalendarControl.DateChanged, _
            AddressOf HandleDateChanged

    End Sub

    Protected Overrides Sub OnUnsubscribeControlEvents(ByVal c As Control)
        ' Call the base method so the basic events are unsubscribed.
        MyBase.OnUnsubscribeControlEvents(c)

        ' Cast the control to a MonthCalendar control.
        Dim monthCalendarControl As MonthCalendar = _
            CType(c, MonthCalendar)

        ' Remove the event.
        RemoveHandler monthCalendarControl.DateChanged, _
            AddressOf HandleDateChanged

    End Sub

    ' Declare the DateChanged event.
    Public Event DateChanged As DateRangeEventHandler

    ' Raise the DateChanged event.
    Private Sub HandleDateChanged(ByVal sender As Object, _
        ByVal e As DateRangeEventArgs)

        RaiseEvent DateChanged(Me, e)
    End Sub
End Class

    //Declare a class that inherits from ToolStripControlHost.
    public class ToolStripMonthCalendar : ToolStripControlHost
    {
        // Call the base constructor passing in a MonthCalendar instance.
        public ToolStripMonthCalendar() : base (new MonthCalendar()) { }

        public MonthCalendar MonthCalendarControl
        {
            get
            {
                return Control as MonthCalendar;
            }
        }

        // Expose the MonthCalendar.FirstDayOfWeek as a property.
        public Day FirstDayOfWeek
        {
            get
            {
                return MonthCalendarControl.FirstDayOfWeek;
            }
            set { MonthCalendarControl.FirstDayOfWeek = value; }
        }

        // Expose the AddBoldedDate method.
        public void AddBoldedDate(DateTime dateToBold)
        {
            MonthCalendarControl.AddBoldedDate(dateToBold);
        }

        // Subscribe and unsubscribe the control events you wish to expose.
        protected override void OnSubscribeControlEvents(Control c)
        {
            // Call the base so the base events are connected.
            base.OnSubscribeControlEvents(c);

            // Cast the control to a MonthCalendar control.
            MonthCalendar monthCalendarControl = (MonthCalendar) c;

            // Add the event.
            monthCalendarControl.DateChanged +=
                new DateRangeEventHandler(OnDateChanged);
        }

        protected override void OnUnsubscribeControlEvents(Control c)
        {
            // Call the base method so the basic events are unsubscribed.
            base.OnUnsubscribeControlEvents(c);

            // Cast the control to a MonthCalendar control.
            MonthCalendar monthCalendarControl = (MonthCalendar) c;

            // Remove the event.
            monthCalendarControl.DateChanged -=
                new DateRangeEventHandler(OnDateChanged);
        }

        // Declare the DateChanged event.
        public event DateRangeEventHandler DateChanged;

        // Raise the DateChanged event.
        private void OnDateChanged(object sender, DateRangeEventArgs e)
        {
            if (DateChanged != null)
            {
                DateChanged(this, e);
            }
        }
    }

//Declare a class that inherits from ToolStripControlHost.
public ref class ToolStripMonthCalendar: public ToolStripControlHost
{
public:
   // Call the base constructor passing in a MonthCalendar instance.
   ToolStripMonthCalendar() : ToolStripControlHost( gcnew MonthCalendar ) {}

   property MonthCalendar^ MonthCalendarControl 
   {
      MonthCalendar^ get()
      {
         return static_cast<MonthCalendar^>(Control);
      }
   }
   property Day FirstDayOfWeek 
   {
      // Expose the MonthCalendar.FirstDayOfWeek as a property.
      Day get()
      {
         return MonthCalendarControl->FirstDayOfWeek;
      }

      void set( Day value )
      {
         MonthCalendarControl->FirstDayOfWeek = value;
      }
   }

   // Expose the AddBoldedDate method.
   void AddBoldedDate( DateTime dateToBold )
   {
      MonthCalendarControl->AddBoldedDate( dateToBold );
   }

protected:
   // Subscribe and unsubscribe the control events you wish to expose.
   void OnSubscribeControlEvents( System::Windows::Forms::Control^ c )
   {
      // Call the base so the base events are connected.
      __super::OnSubscribeControlEvents( c );

      // Cast the control to a MonthCalendar control.
      MonthCalendar^ monthCalendarControl = (MonthCalendar^)c;

      // Add the event.
      monthCalendarControl->DateChanged += gcnew DateRangeEventHandler( this, &ToolStripMonthCalendar::HandleDateChanged );
   }

   void OnUnsubscribeControlEvents( System::Windows::Forms::Control^ c )
   {

      // Call the base method so the basic events are unsubscribed.
      __super::OnUnsubscribeControlEvents( c );

      // Cast the control to a MonthCalendar control.
      MonthCalendar^ monthCalendarControl = (MonthCalendar^)c;

      // Remove the event.
      monthCalendarControl->DateChanged -= gcnew DateRangeEventHandler( this, &ToolStripMonthCalendar::HandleDateChanged );
   }

public:
   event DateRangeEventHandler^ DateChanged;

private:
   // Declare the DateChanged event.
   // Raise the DateChanged event.
   void HandleDateChanged( Object^ sender, DateRangeEventArgs^ e )
   {
      if ( DateChanged != nullptr )
      {
         DateChanged( this, e );
      }
   }
};