EventsTab Class

Definition

Provides a PropertyTab that can display events for selection and linking.

public ref class EventsTab : System::Windows::Forms::Design::PropertyTab
public class EventsTab : System.Windows.Forms.Design.PropertyTab
type EventsTab = class
    inherit PropertyTab
Public Class EventsTab
Inherits PropertyTab
Inheritance
EventsTab

Examples

The following code example provides an example EventsTab. When selected, the EventsTab lists any events on a component in order of delegate type.

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

using namespace System;
using namespace System::ComponentModel;
using namespace System::ComponentModel::Design;
using namespace System::Collections;
using namespace System::Drawing;
using namespace System::IO;
using namespace System::Reflection;
using namespace System::Runtime::Serialization;
using namespace System::Runtime::Serialization::Formatters::Binary;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::Design;

ref class TypeEventsTab;

// This component adds a TypeEventsTab to the Properties Window.

[PropertyTabAttribute(TypeEventsTab::typeid,PropertyTabScope::Document)]
public ref class TypeEventsTabComponent: public Component
{
public:
   TypeEventsTabComponent(){}

};


// This example events tab lists events by their delegate type.
[System::Security::Permissions::PermissionSetAttribute
      (System::Security::Permissions::SecurityAction::InheritanceDemand, Name="FullTrust")]
[System::Security::Permissions::PermissionSetAttribute
      (System::Security::Permissions::SecurityAction::Demand, Name="FullTrust")]
public ref class TypeEventsTab: public System::Windows::Forms::Design::EventsTab
{
private:

   // This string contains a Base-64 encoded and serialized example 
   // property tab image.

   [BrowsableAttribute(true)]
   String^ img;
   IServiceProvider^ sp;

public:
   TypeEventsTab( IServiceProvider^ sp )
      : EventsTab( sp )
   {
      this->sp = sp;
      String^ s = "AAEAAAD/////AQAAAAAAAAAMAgAAAFRTeXN0ZW0uRHJhd2luZywgVmVyc2lvbj0xLjAuMzMwMC4w"
      "LCBDdWx0dXJlPW5ldXRyYWwsIFB1YmxpY0tleVRva2VuPWIwM2Y1ZjdmMTFkNTBhM2EFAQAAABVTeXN0ZW0uRHJhd2luZy5CaXRt"
      "YXABAAAABERhdGEHAgIAAAAJAwAAAA8DAAAAtgIAAAJCTbYCAAAAAAAANgAAACgAAAANAAAAEAAAAAEAGAAAAAAAAAAAAMQOAADED"
      "gAAAAAAAAAAAADO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tn/ztbZztbZHh4eHh4eztbZztbZztbZztbZztb"
      "ZztbZztbZztbZztbZ/87W2c7W2QDBAB4eHh4eHs7W2c7W2c7W2c7W2c7W2c7W2c7W2c7W2f/O1tnO1tnO1tkAwQAeHh4eHh7O1tnO1"
      "tnO1tnO1tnO1tnO1tnO1tn/ztbZztbZlJSU////AMEAHh4eHh4eztbZztbZztbZztbZztbZztbZ/87W2c7W2c7W2ZSUlP///wDBAB4"
      "eHh4eHs7W2c7W2c7W2c7W2c7W2f/O1tnO1tnO1tnO1tmUlJT///8AwQAeHh4eHh7O1tnO1tnO1tnO1tn/ztbZHh4eHh4eHh4eHh4eH"
      "h4e////AIAAHh4eHh4eztbZztbZztbZ/87W2ZSUlP///wDBAADBAADBAADBAADBAACAAB4eHh4eHs7W2c7W2f/O1tnO1tmUlJT///8"
      "AwQAAgAAeHh4eHh7O1tnO1tnO1tnO1tnO1tn/ztbZztbZztbZlJSU////AMEAAIAAHh4eHh4eztbZztbZztbZztbZ/87W2c7W2c7W2"
      "c7W2ZSUlP///wDBAACAAB4eHh4eHs7W2c7W2c7W2f/O1tnO1tnO1tnO1tnO1tmUlJT///8AwQAAgAAeHh4eHh7O1tnO1tn/ztbZztb"
      "ZztbZztbZztbZztbZlJSU////AMEAAIAAHh4eHh4eztbZ/87W2c7W2c7W2c7W2c7W2c7W2c7W2ZSUlP///wDBAACAAB4eHs7W2f/O1"
      "tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tnO1tn/Cw==";
      img = s;
   }

   // Returns the properties of the specified component extended with a 
   // CategoryAttribute reflecting the name of the type of the property.
   virtual System::ComponentModel::PropertyDescriptorCollection^ GetProperties( ITypeDescriptorContext^ /*context*/, Object^ component, array<System::Attribute^>^attributes ) override
   {
      // Obtain an instance of the IEventBindingService.
      IEventBindingService^ eventPropertySvc = dynamic_cast<IEventBindingService^>(sp->GetService( IEventBindingService::typeid ));
      
      // Return if an IEventBindingService could not be obtained.
      if ( eventPropertySvc == nullptr )
            return gcnew PropertyDescriptorCollection( nullptr );

      // Obtain the events on the component.
      EventDescriptorCollection^ events = TypeDescriptor::GetEvents( component, attributes );

      // Create an array of the events, where each event is assigned 
      // a category matching its type.
      array<EventDescriptor^>^newEvents = gcnew array<EventDescriptor^>(events->Count);
      for ( int i = 0; i < events->Count; i++ )
      {
         array<Attribute^>^temp = {gcnew CategoryAttribute( events[ i ]->EventType->FullName )};
         newEvents[ i ] = TypeDescriptor::CreateEvent( events[ i ]->ComponentType, events[ i ], temp );
      }
      events = gcnew EventDescriptorCollection( newEvents );

      // Return event properties for the event descriptors.
      return eventPropertySvc->GetEventProperties( events );
   }

   property String^ TabName 
   {
      // Provides the name for the event property tab.
      virtual String^ get() override
      {
         return "Events by Type";
      }
   }

   property System::Drawing::Bitmap^ Bitmap 
   {
      // Provides an image for the event property tab.
      virtual System::Drawing::Bitmap^ get() override
      {
         System::Drawing::Bitmap^ bmp = gcnew System::Drawing::Bitmap( DeserializeFromBase64Text( img ) );
         return bmp;
      }
   }

private:

   // This method can be used to retrieve an Image from a block of 
   // Base64-encoded text.
   Image^ DeserializeFromBase64Text( String^ text )
   {
      Image^ img = nullptr;
      array<Byte>^memBytes = Convert::FromBase64String( text );
      IFormatter^ formatter = gcnew BinaryFormatter;
      MemoryStream^ stream = gcnew MemoryStream( memBytes );
      img = dynamic_cast<Image^>(formatter->Deserialize( stream ));
      stream->Close();
      return img;
   }
};
using System;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Collections;
using System.Drawing;
using System.IO;
using System.Reflection;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using System.Windows.Forms;
using System.Windows.Forms.Design;

namespace EventsTabExample
{    
    // This component adds a TypeEventsTab to the Properties Window.
    [PropertyTabAttribute(typeof(TypeEventsTab), PropertyTabScope.Document)]
    public class TypeEventsTabComponent : Component
    {
        public TypeEventsTabComponent()
        {
        }
    }

    // This example events tab lists events by their delegate type.
    [System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.InheritanceDemand, Name="FullTrust")]
    [System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
    public class TypeEventsTab : System.Windows.Forms.Design.EventsTab
    {
        [BrowsableAttribute(true)]
        // This string contains a Base-64 encoded and serialized example 
        // property tab image.
        private string img = "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";
        private IServiceProvider sp;

        public TypeEventsTab(IServiceProvider sp) : base(sp)
        {
            this.sp = sp;           
        }
                  
        // Returns the properties of the specified component extended with a 
        // CategoryAttribute reflecting the name of the type of the property.
        public override System.ComponentModel.PropertyDescriptorCollection 
            GetProperties(ITypeDescriptorContext context, object component, 
            System.Attribute[] attributes)
        {            
            // Obtain an instance of the IEventBindingService.
            IEventBindingService eventPropertySvc = (IEventBindingService)
                sp.GetService(typeof(IEventBindingService));

            // Return if an IEventBindingService could not be obtained.
            if (eventPropertySvc == null)             
                return new PropertyDescriptorCollection(null);
            
            // Obtain the events on the component.
            EventDescriptorCollection events = 
                TypeDescriptor.GetEvents(component, attributes);       
     
            // Create an array of the events, where each event is assigned 
            // a category matching its type.
            EventDescriptor[] newEvents = new EventDescriptor[events.Count];
            for(int i=0;i < events.Count;i++)             
                newEvents[i] = TypeDescriptor.CreateEvent(events[i].ComponentType, events[i], 
                    new CategoryAttribute(events[i].EventType.FullName));            
            events = new EventDescriptorCollection(newEvents);

            // Return event properties for the event descriptors.
            return eventPropertySvc.GetEventProperties(events);
        }        

        // Provides the name for the event property tab.
        public override string TabName
        {
            get
            {
                return "Events by Type";
            }
        }

        // Provides an image for the event property tab.
        public override System.Drawing.Bitmap Bitmap
        {
            get
            {
                Bitmap bmp = new Bitmap(DeserializeFromBase64Text(img));
                return bmp;
            }
        }

        // This method can be used to retrieve an Image from a block of 
        // Base64-encoded text.
        private Image DeserializeFromBase64Text(string text)
        {
            Image img = null;
            byte[] memBytes = Convert.FromBase64String(text);
            IFormatter formatter = new BinaryFormatter();
            MemoryStream stream = new MemoryStream(memBytes);
            img = (Image)formatter.Deserialize(stream);
            stream.Close();
            return img;
        }
    }
}

Constructors

EventsTab(IServiceProvider)

Initializes a new instance of the EventsTab class.

Properties

Bitmap

Gets the bitmap that is displayed for the PropertyTab.

(Inherited from PropertyTab)
Components

Gets or sets the array of components the property tab is associated with.

(Inherited from PropertyTab)
HelpKeyword

Gets the Help keyword for the tab.

TabName

Gets the name of the tab.

Methods

CanExtend(Object)

Gets a value indicating whether the specified object can be extended.

Dispose()

Releases all the resources used by the PropertyTab.

(Inherited from PropertyTab)
Dispose(Boolean)

Releases the unmanaged resources used by the PropertyTab and optionally releases the managed resources.

(Inherited from PropertyTab)
Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetDefaultProperty(Object)

Gets the default property from the specified object.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetProperties(ITypeDescriptorContext, Object, Attribute[])

Gets all the properties of the event tab that match the specified attributes and context.

GetProperties(Object)

Gets the properties of the specified component.

(Inherited from PropertyTab)
GetProperties(Object, Attribute[])

Gets all the properties of the event tab that match the specified attributes.

GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to