IEventBindingService Rozhraní

Definice

public interface class IEventBindingService

public interface IEventBindingService

[System.Runtime.InteropServices.ComVisible(true)]
public interface IEventBindingService

type IEventBindingService = interface

[<System.Runtime.InteropServices.ComVisible(true)>]
type IEventBindingService = interface

Public Interface IEventBindingService

Odvozené

System.ComponentModel.Design.EventBindingService

Atributy

ComVisibleAttribute

Příklady

Následující příklad ukazuje návrhář, který používá IEventBindingService k propojení události komponenty s obslužnou rutinou události v době návrhu při vyvolání vlastního příkazu místní nabídky, který návrhář přidá pro komponentu. Chcete-li použít příklad, zkompilujte jej do knihovny tříd, přidejte odkaz z model Windows Forms projektu, přidejte komponentu v knihovně tříd do sady nástrojů tak, že kliknete pravým tlačítkem myši na panel nástrojů a vyberete Přizpůsobit sadu nástrojů, pak zvolíte knihovnu tříd a kliknete na TLAČÍTKO OK a přidáte instanci EventControl do formuláře. Potom klikněte pravým tlačítkem na EventControl a klikněte na příkaz místní nabídky Připojit testEvent. Je vytvořena prázdná metoda obslužné rutiny události a metoda eventControl testEvent je inicializována do této obslužné rutiny události v inicializačním kódu formuláře.

#using <System.Windows.Forms.dll>
#using <System.Data.dll>
#using <System.Drawing.dll>
#using <System.Design.dll>
#using <System.dll>

using namespace System;
using namespace System::Collections;
using namespace System::ComponentModel;
using namespace System::ComponentModel::Design;
using namespace System::Drawing;
using namespace System::Data;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::Design;
using namespace System::Security::Permissions;

// This designer provides a "Connect testEvent" designer verb shortcut 
// menu command. When invoked, the command attaches a new event-handler 
// method named "testEventHandler" to the "testEvent" event of an 
// associated control.
// If a "testEvent" event of the associated control does not exist, 
// the IEventBindingService declares it.
public ref class EventDesigner: public System::Windows::Forms::Design::ControlDesigner
{
public:
   EventDesigner(){}

   // When the "Connect testEvent" designer verb shortcut menu 
   // command is invoked, this method uses the 
   // IEventBindingService to attach an event handler to a 
   // "textEvent" event of the associated control.
private:
   void ConnectEvent( Object^ /*sender*/, EventArgs^ /*e*/ )
   {
      IEventBindingService^ eventservice = dynamic_cast<IEventBindingService^>(this->Component->Site->GetService( System::ComponentModel::Design::IEventBindingService::typeid ));
      if ( eventservice != nullptr )
      {
         // Attempt to obtain a PropertyDescriptor for a 
         // component event named "testEvent".
         EventDescriptorCollection^ edc = TypeDescriptor::GetEvents( this->Component );
         if ( edc == nullptr || edc->Count == 0 )
                  return;
         EventDescriptor^ ed = nullptr;

         // Search for an event named "testEvent".
         IEnumerator^ myEnum = edc->GetEnumerator();
         while ( myEnum->MoveNext() )
         {
            EventDescriptor^ edi = safe_cast<EventDescriptor^>(myEnum->Current);
            if ( edi->Name->Equals( "testEvent" ) )
            {
               ed = edi;
               break;
            }
         }
         if ( ed == nullptr )
                  return;

         // Use the IEventBindingService to get a 
         // PropertyDescriptor for the event.
         PropertyDescriptor^ pd = eventservice->GetEventProperty( ed );
         if ( pd == nullptr )
                  return;

         // Set the value of the event to "testEventHandler".
         pd->SetValue( this->Component, "testEventHandler" );
      }
   }

public:
   property System::ComponentModel::Design::DesignerVerbCollection^ Verbs 
   {
      // Provides a designer verb command for the designer's 
      // shortcut menu.
      [PermissionSetAttribute(SecurityAction::Demand, Name="FullTrust")]
      virtual System::ComponentModel::Design::DesignerVerbCollection^ get() override
      {
         DesignerVerbCollection^ dvc = gcnew DesignerVerbCollection;
         dvc->Add( gcnew DesignerVerb( "Connect testEvent",gcnew EventHandler( this, &EventDesigner::ConnectEvent ) ) );
         return dvc;
      }
   }
};

// EventControl is associated with the EventDesigner and displays 
// instructions for demonstrating the service.

[Designer(EventDesigner::typeid)]
public ref class EventControl: public System::Windows::Forms::UserControl
{
public:
   event System::EventHandler^ testEvent;
   EventControl()
   {
      this->BackColor = Color::White;
      this->Size = System::Drawing::Size( 320, 96 );
   }

public:
   ~EventControl()
   {
   }

protected:
   virtual void OnPaint( System::Windows::Forms::PaintEventArgs^ e ) override
   {
      e->Graphics->DrawString( "IEventBindingService Example Control", gcnew System::Drawing::Font( FontFamily::GenericMonospace,10 ), gcnew SolidBrush( Color::Blue ), 5, 5 );
      e->Graphics->DrawString( "Use the \"Connect testEvent\" command of the", gcnew System::Drawing::Font( FontFamily::GenericMonospace,8 ), gcnew SolidBrush( Color::Black ), 5, 22 );
      e->Graphics->DrawString( "right-click shortcut menu provided by this", gcnew System::Drawing::Font( FontFamily::GenericMonospace,8 ), gcnew SolidBrush( Color::Black ), 5, 32 );
      e->Graphics->DrawString( "control's associated EventDesigner to create", gcnew System::Drawing::Font( FontFamily::GenericMonospace,8 ), gcnew SolidBrush( Color::Black ), 5, 42 );
      e->Graphics->DrawString( "a new event handler linked with the testEvent", gcnew System::Drawing::Font( FontFamily::GenericMonospace,8 ), gcnew SolidBrush( Color::Black ), 5, 52 );
      e->Graphics->DrawString( "of this control in the initialization code", gcnew System::Drawing::Font( FontFamily::GenericMonospace,8 ), gcnew SolidBrush( Color::Black ), 5, 62 );
      e->Graphics->DrawString( "for this control.", gcnew System::Drawing::Font( FontFamily::GenericMonospace,8 ), gcnew SolidBrush( Color::Black ), 5, 72 );
   }
};

using System;
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Drawing;
using System.Data;
using System.Windows.Forms;
using System.Windows.Forms.Design;

namespace EventDesignerTest
{
    // This designer provides a "Connect testEvent" designer verb shortcut 
    // menu command. When invoked, the command attaches a new event-handler 
    // method named "testEventHandler" to the "testEvent" event of an 
    // associated control.
    // If a "testEvent" event of the associated control does not exist, 
    // the IEventBindingService declares it.
    public class EventDesigner : System.Windows.Forms.Design.ControlDesigner
    {
        public EventDesigner()
        {
        }
        
        // When the "Connect testEvent" designer verb shortcut menu 
        // command is invoked, this method uses the 
        // IEventBindingService to attach an event handler to a 
        // "textEvent" event of the associated control.
        private void ConnectEvent(object sender, EventArgs e)
        {
            IEventBindingService eventservice = (IEventBindingService)this.Component.Site.GetService(typeof(System.ComponentModel.Design.IEventBindingService));
            if( eventservice != null )
            {
                // Attempt to obtain a PropertyDescriptor for a 
                // component event named "testEvent".
                EventDescriptorCollection edc = TypeDescriptor.GetEvents(this.Component);				
                if( edc == null || edc.Count == 0 )
                    return;
                                
                EventDescriptor ed = null;
                // Search for an event named "testEvent".
                foreach(EventDescriptor edi in edc)
                    if(edi.Name == "testEvent")
                    {
                        ed = edi;
                        break;
                    }
                if( ed == null )
                    return;

                // Use the IEventBindingService to get a 
                // PropertyDescriptor for the event.
                PropertyDescriptor pd = eventservice.GetEventProperty(ed);
                if( pd == null )
                    return;				
                
                // Set the value of the event to "testEventHandler".
                pd.SetValue(this.Component, "testEventHandler");
            }
        }

                // Provides a designer verb command for the designer's 
                // shortcut menu.
        public override System.ComponentModel.Design.DesignerVerbCollection Verbs
        {
            get
            {
                DesignerVerbCollection dvc = new DesignerVerbCollection();
                dvc.Add(new DesignerVerb("Connect testEvent", new EventHandler(ConnectEvent)));
                return dvc;
            }
        }
    }

    // EventControl is associated with the EventDesigner and displays 
    // instructions for demonstrating the service.
    [Designer(typeof(EventDesigner))]
    public class EventControl : System.Windows.Forms.UserControl
    {
        public event System.EventHandler testEvent;

        public EventControl()
        {		
            this.BackColor = Color.White;	
            this.Size = new Size(320, 96);
        }

        protected override void Dispose( bool disposing )
        {
            base.Dispose( disposing );
        }

        protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
        {
            e.Graphics.DrawString("IEventBindingService Example Control", new Font(FontFamily.GenericMonospace, 10), new SolidBrush(Color.Blue), 5, 5);
            
            e.Graphics.DrawString("Use the \"Connect testEvent\" command of the", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 5, 22);
            e.Graphics.DrawString("right-click shortcut menu provided by this", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 5, 32);
            e.Graphics.DrawString("control's associated EventDesigner to create", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 5, 42);
            e.Graphics.DrawString("a new event handler linked with the testEvent", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 5, 52);
            e.Graphics.DrawString("of this control in the initialization code", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 5, 62);
            e.Graphics.DrawString("for this control.", new Font(FontFamily.GenericMonospace, 8), new SolidBrush(Color.Black), 5, 72);
        }
    }
}

Imports System.Collections
Imports System.ComponentModel
Imports System.ComponentModel.Design
Imports System.Data
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.Design

Namespace EventDesignerTest
    ' This designer provides a "Connect testEvent" designer verb shortcut 
    ' menu command. When invoked, the command attaches a new event-handler 
    ' method named "testEventHandler" to the "testEvent" event of an 
    ' associated control.
    ' If a "testEvent" event of the associated control does not exist, 
    ' the IEventBindingService declares it.
    <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
    Public Class EventDesigner
        Inherits System.Windows.Forms.Design.ControlDesigner

        Public Sub New()
        End Sub

        ' When the "Connect testEvent" designer verb shortcut menu 
        ' command is invoked, this method uses the 
        ' IEventBindingService to attach an event handler to a "textEvent" event of the associated control.
        Private Sub ConnectEvent(ByVal sender As Object, ByVal e As EventArgs)
            Dim eventservice As IEventBindingService = CType(Me.Component.Site.GetService(GetType(System.ComponentModel.Design.IEventBindingService)), IEventBindingService)
            If (eventservice IsNot Nothing) Then
                ' Attempt to obtain a PropertyDescriptor for a 
                ' component event named "testEvent".
                Dim edc As EventDescriptorCollection = TypeDescriptor.GetEvents(Me.Component)
                If edc Is Nothing Or edc.Count = 0 Then
                    Return
                End If
                Dim ed As EventDescriptor = Nothing
                ' Search for an event named "testEvent".
                Dim edi As EventDescriptor
                For Each edi In edc
                    If edi.Name = "testEvent" Then
                        ed = edi
                        Exit For
                    End If
                Next edi
                If ed Is Nothing Then
                    Return
                End If
                ' Use the IEventBindingService to get a 
                ' PropertyDescriptor for the event.
                Dim pd As PropertyDescriptor = eventservice.GetEventProperty(ed)
                If pd Is Nothing Then
                    Return
                End If
                ' Set the value of the event to "testEventHandler".
                pd.SetValue(Me.Component, "testEventHandler")
            End If
        End Sub

        ' Provides a designer verb command for the designer's 
        ' shortcut menu.
        Public Overrides ReadOnly Property Verbs() As System.ComponentModel.Design.DesignerVerbCollection
            Get
                Dim dvc As New DesignerVerbCollection()
                dvc.Add(New DesignerVerb("Connect testEvent", New EventHandler(AddressOf ConnectEvent)))
                Return dvc
            End Get
        End Property
    End Class

    ' EventControl is associated with the EventDesigner and displays 
    ' instructions for demonstrating the service.
    <Designer(GetType(EventDesigner))> _
    Public Class EventControl
        Inherits System.Windows.Forms.UserControl
        Public Event testEvent As System.EventHandler

        Public Sub New()
            Me.BackColor = Color.White
            Me.Size = New Size(320, 96)
        End Sub

        Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
            MyBase.Dispose(disposing)
        End Sub

        Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)
            e.Graphics.DrawString("IEventBindingService Example Control", New Font(FontFamily.GenericMonospace, 10), New SolidBrush(Color.Blue), 5, 5)
            e.Graphics.DrawString("Use the ""Connect testEvent"" command of the", New Font(FontFamily.GenericMonospace, 8), New SolidBrush(Color.Black), 5, 22)
            e.Graphics.DrawString("right-click shortcut menu provided by this", New Font(FontFamily.GenericMonospace, 8), New SolidBrush(Color.Black), 5, 32)
            e.Graphics.DrawString("control's associated EventDesigner to create", New Font(FontFamily.GenericMonospace, 8), New SolidBrush(Color.Black), 5, 42)
            e.Graphics.DrawString("a new event handler linked with the testEvent", New Font(FontFamily.GenericMonospace, 8), New SolidBrush(Color.Black), 5, 52)
            e.Graphics.DrawString("of this control in the initialization code", New Font(FontFamily.GenericMonospace, 8), New SolidBrush(Color.Black), 5, 62)
            e.Graphics.DrawString("for this control.", New Font(FontFamily.GenericMonospace, 8), New SolidBrush(Color.Black), 5, 72)
        End Sub

    End Class
End Namespace

Poznámky

Služba vazby událostí poskytuje způsob, jak propojit obslužnou rutinu události s událostí komponenty z kódu návrháře.

Chcete-li propojit obslužnou rutinu události s událostí komponenty pomocí IEventBindingService, musíte nejprve získat EventDescriptor objekt pro událost komponenty, kterou chcete propojit. Poskytuje IEventBindingService metody, které mohou převést na EventDescriptor objekt PropertyDescriptor , který můžete použít ke konfiguraci události s názvem metody obslužné rutiny události.

Objekt TypeDescriptor poskytuje metodu GetEvents , kterou můžete použít k získání EventDescriptorCollection obsahujících EventDescriptor objektů pro každou událost komponenty. Metody GetEventPropertyIEventBindingService a GetEventProperties vrátí PropertyDescriptor hodnotu pro každou z nich EventDescriptor předanou některé z metod. Každý PropertyDescriptor vrácený z GetEventProperty nebo GetEventProperties má typ vlastnosti řetězec. Tento řetězec můžete nastavit na hodnotu, která určuje název metody obslužné rutiny události pro propojení události s pomocí SetValue metody PropertyDescriptor.

Metody

Platí pro

Viz také

• PropertyDescriptor
• EventDescriptor
• PropertyDescriptorCollection
• EventDescriptorCollection