IEventBindingService Rozhraní
Definice
Důležité
Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.
Poskytuje službu pro registraci obslužných rutin událostí pro události komponent.
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
- Atributy
Příklady
Následující příklad ukazuje návrháře, který používá IEventBindingService k propojení události komponenty s obslužnou rutinou události v době návrhu, když je vyvolán vlastní příkaz místní nabídky, který návrhář přidá pro komponentu. Pokud chcete tento příklad použít, zkompilujte ho do knihovny tříd. přidejte odkaz z projektu model Windows Forms, přidejte komponentu v knihovně tříd do sady nástrojů tak, že kliknete pravým tlačítkem myši na Toolbox a vyberete Customize Toolbox, vyberete knihovnu tříd a kliknete na OK, a přidejte instanci EventControl do formuláře. Potom klikněte pravým tlačítkem na EventControl a klikněte na příkaz místní nabídky Connect testEvent. Vytvoří se prázdná metoda obslužné rutiny události a metoda TestEvent třídy EventControl se inicializuje na tuto obslužnou rutinu 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 událost komponenty, kterou chcete propojit. Poskytuje IEventBindingService metody, které mohou převést EventDescriptor na , PropertyDescriptorkterý 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 GetEventProperty vrácení GetEventPropertiesIEventBindingServicePropertyDescriptor pro každou z těchto EventDescriptor metod. Každý PropertyDescriptor vrácený z GetEventProperty nebo GetEventProperties má typ vlastnosti řetězce. Tento řetězec můžete nastavit na hodnotu, která označuje název metody obslužné rutiny událostí pro propojení události s použitím SetValue metody PropertyDescriptor.
Metody
| Name | Description |
|---|---|
| CreateUniqueMethodName(IComponent, EventDescriptor) |
Vytvoří jedinečný název pro metodu obslužné rutiny události pro zadanou komponentu a událost. |
| GetCompatibleMethods(EventDescriptor) |
Získá kolekci metod obslužné rutiny událostí, které mají podpis metody kompatibilní se zadanou událostí. |
| GetEvent(PropertyDescriptor) |
EventDescriptor Získá pro událost, že zadaný popisovač vlastnosti představuje, pokud představuje událost. |
| GetEventProperties(EventDescriptorCollection) |
Převede sadu popisovačů událostí na sadu popisovačů vlastností. |
| GetEventProperty(EventDescriptor) |
Převede jeden popisovač události na popisovač vlastnosti. |
| ShowCode() |
Zobrazí uživatelský kód pro návrháře. |
| ShowCode(IComponent, EventDescriptor) |
Zobrazí uživatelský kód pro zadanou událost. |
| ShowCode(Int32) |
Zobrazí uživatelský kód návrháře na zadaném řádku. |