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IComponent Interface

Provides functionality required by all components.

Namespace:  System.ComponentModel
Assembly:  System (in System.dll)

[TypeConverterAttribute(typeof(ComponentConverter))]
[ComVisibleAttribute(true)]
public interface class IComponent : IDisposable

Component is the default implementation of IComponent and serves as the base class for all components in the common language runtime.

You can contain components in a container. In this context, containment refers to logical containment, not visual containment. You can use components and containers in a variety of scenarios, both visual and non visual.

System.Windows.Forms::Control inherits from Component, the default implementation of IComponent.

A component interacts with its container primarily through a container-provided ISite, which is a repository of container-specific per-component information.

Notes to Implementers:

To be a component, a class must implement the IComponent interface and provide a basic constructor that requires no parameters or a single parameter of type IContainer. For more information about implementing IComponent, see Programming with Components.

The following code example demonstrates how to implement the IComponent, ISite, and IContainer interfaces.

/// <summary> 
/// The following example demonstrates the implementation of 
/// ISite, IComponent, and IContainer for use in a simple library container. 
/// 
/// This example uses the System, System.ComponentModel, and System.Collections 
/// namespaces. 
/// </summary> 
//This code segment implements the ISite and IComponent interfaces. 
//The implementation of the IContainer interface can be seen in the documentation 
//of IContainer. 
//Implement the ISite interface. 
// The ISBNSite class represents the ISBN name of the book component 
ref class ISBNSite: public ISite
{
private:
   IComponent^ m_curComponent;
   IContainer^ m_curContainer;
   bool m_bDesignMode;
   String^ m_ISBNCmpName;

public:
   ISBNSite( IContainer^ actvCntr, IComponent^ prntCmpnt )
   {
      m_curComponent = prntCmpnt;
      m_curContainer = actvCntr;
      m_bDesignMode = false;
      m_ISBNCmpName = nullptr;
   }


   property IComponent^ Component 
   {

      //Support the ISite interface. 
      virtual IComponent^ get()
      {
         return m_curComponent;
      }

   }

   property IContainer^ Container 
   {
      virtual IContainer^ get()
      {
         return m_curContainer;
      }

   }

   property bool DesignMode 
   {
      virtual bool get()
      {
         return m_bDesignMode;
      }

   }

   property String^ Name 
   {
      virtual String^ get()
      {
         return m_ISBNCmpName;
      }

      virtual void set( String^ value )
      {
         m_ISBNCmpName = value;
      }

   }

   //Support the IServiceProvider interface. 
   virtual Object^ GetService( Type^ serviceType )
   {

      //This example does not use any service object. 
      return nullptr;
   }

};


// The BookComponent class represents the book component of the library container. 
// This class implements the IComponent interface. 
ref class BookComponent: public IComponent
{
private:
   ISite^ m_curISBNSite;
   String^ m_bookTitle;
   String^ m_bookAuthor;

public:
   event virtual EventHandler^ Disposed;
   BookComponent( String^ Title, String^ Author )
   {
      m_curISBNSite = nullptr;
      Disposed = nullptr;
      m_bookTitle = Title;
      m_bookAuthor = Author;
   }


   property String^ Title 
   {
      String^ get()
      {
         return m_bookTitle;
      }

   }

   property String^ Author 
   {
      String^ get()
      {
         return m_bookAuthor;
      }

   }

   ~BookComponent()
   {
      //There is nothing to clean. 
      if ( Disposed != nullptr )
               Disposed( this, EventArgs::Empty );
   }

   property ISite^ Site 
   {
      virtual ISite^ get()
      {
         return m_curISBNSite;
      }

      virtual void set( ISite^ value )
      {
         m_curISBNSite = value;
      }

   }
   virtual bool Equals( Object^ cmp ) override
   {
      BookComponent^ cmpObj = safe_cast<BookComponent^>(cmp);
      return (this->Title->Equals( cmpObj->Title ) && this->Author->Equals( cmpObj->Author ));
   }

   virtual int GetHashCode() override
   {
      return IComponent::GetHashCode();
   }

};

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
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