IContainer Interface

 

Provides functionality for containers. Containers are objects that logically contain zero or more components.

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

[ComVisibleAttribute(true)]
public interface class IContainer : IDisposable

NameDescription
System_CAPS_pubpropertyComponents

Gets all the components in the IContainer.

NameDescription
System_CAPS_pubmethodAdd(IComponent^)

Adds the specified IComponent to the IContainer at the end of the list.

System_CAPS_pubmethodAdd(IComponent^, String^)

Adds the specified IComponent to the IContainer at the end of the list, and assigns a name to the component.

System_CAPS_pubmethodDispose()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.(Inherited from IDisposable.)

System_CAPS_pubmethodRemove(IComponent^)

Removes a component from the IContainer.

Containers are objects that encapsulate and track zero or more components. In this context, containment refers to logical containment, not visual containment. You can use components and containers in a variety of scenarios, including scenarios that are both visual and not visual.

Notes to Implementers:

To be a container, the class must implement the IContainer interface, which supports methods for adding, removing, and retrieving components.

The following code example demonstrates how to implement the IContainer interface.

 //This code segment implements the IContainer interface.  The code segment
 //containing the implementation of ISite and IComponent can be found in the documentation
 //for those interfaces.
 //Implement the LibraryContainer using the IContainer interface.
 ref class LibraryContainer: public IContainer
 {
 private:
    ArrayList^ m_bookList;

 public:
    LibraryContainer()
    {
       m_bookList = gcnew ArrayList;
    }

    virtual void Add( IComponent^ book )
    {

       //The book will be added without creation of the ISite object.
       m_bookList->Add( book );
    }

    virtual void Add( IComponent^ book, String^ ISNDNNum )
    {
       for ( int i = 0; i < m_bookList->Count; ++i )
       {
          IComponent^ curObj = static_cast<IComponent^>(m_bookList->default[ i ]);
          if ( curObj->Site != nullptr )
          {
             if ( curObj->Site->Name->Equals( ISNDNNum ) )
                            throw gcnew SystemException( "The ISBN number already exists in the container" );
          }

       }
       ISBNSite^ data = gcnew ISBNSite( this,book );
       data->Name = ISNDNNum;
       book->Site = data;
       m_bookList->Add( book );
    }

    virtual void Remove( IComponent^ book )
    {
       for ( int i = 0; i < m_bookList->Count; ++i )
       {
          if ( book->Equals( m_bookList->default[ i ] ) )
          {
             m_bookList->RemoveAt( i );
             break;
          }

       }
    }


    property ComponentCollection^ Components 
    {
       virtual ComponentCollection^ get() 
       {
          array<IComponent^>^datalist = gcnew array<BookComponent^>(m_bookList->Count);
          m_bookList->CopyTo( datalist );
          return gcnew ComponentCollection( datalist );
       }

    }

    ~LibraryContainer()
    {
       for ( int i = 0; i < m_bookList->Count; ++i )
       {
          IComponent^ curObj = static_cast<IComponent^>(m_bookList->default[ i ]);
          delete curObj;

       }
       m_bookList->Clear();
    }



 };



 [STAThreadAttribute]
 int main()
    {
       LibraryContainer^ cntrExmpl = gcnew LibraryContainer;
       try
       {
          BookComponent^ book1 = gcnew BookComponent( "Wizard's First Rule","Terry Gooodkind" );
          cntrExmpl->Add( book1, "0812548051" );
          BookComponent^ book2 = gcnew BookComponent( "Stone of Tears","Terry Gooodkind" );
          cntrExmpl->Add( book2, "0812548094" );
          BookComponent^ book3 = gcnew BookComponent( "Blood of the Fold","Terry Gooodkind" );
          cntrExmpl->Add( book3, "0812551478" );
          BookComponent^ book4 = gcnew BookComponent( "The Soul of the Fire","Terry Gooodkind" );

          //This will generate exception because the ISBN already exists in the container.
          cntrExmpl->Add( book4, "0812551478" );
       }
       catch ( SystemException^ e ) 
       {
          Console::WriteLine(  "Error description: {0}", e->Message );
       }

       ComponentCollection^ datalist = cntrExmpl->Components;
       IEnumerator^ denum = datalist->GetEnumerator();
       while ( denum->MoveNext() )
       {
          BookComponent^ cmp = static_cast<BookComponent^>(denum->Current);
          Console::WriteLine( "Book Title: {0}", cmp->Title );
          Console::WriteLine(  "Book Author: {0}", cmp->Author );
          Console::WriteLine(  "Book ISBN: {0}", cmp->Site->Name );
       }

return 0;
    }

.NET Framework
Available since 1.1
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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