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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 IComponent : IDisposable
/** @attribute TypeConverterAttribute(System.ComponentModel.ComponentConverter) */ 
/** @attribute ComVisibleAttribute(true) */ 
public interface IComponent extends IDisposable
TypeConverterAttribute(System.ComponentModel.ComponentConverter) 
ComVisibleAttribute(true) 
public interface IComponent extends IDisposable
Not applicable.

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
class ISBNSite : ISite
{
    private IComponent m_curComponent;
    private IContainer m_curContainer;
    private bool m_bDesignMode;
    private string m_ISBNCmpName;

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

    //Support the ISite interface.
    public virtual IComponent Component
    {
        get
        {
            return m_curComponent;
        }
    }

    public virtual IContainer Container
    {
        get
        {
            return m_curContainer;
        }
    }
    
    public virtual bool DesignMode
    {
        get
        {
            return m_bDesignMode;
        }
    }

    public virtual string Name
    {
        get
        {
            return m_ISBNCmpName;
        }

        set
        {
            m_ISBNCmpName = value;
        }
    }

    //Support the IServiceProvider interface.
    public virtual object GetService(Type serviceType)
    {
        //This example does not use any service object.
        return null;
    }

}

// The BookComponent class represents the book component of the library container.

// This class implements the IComponent interface.

class BookComponent : IComponent
{
    public event EventHandler Disposed;
    private ISite m_curISBNSite;
    private string m_bookTitle;
    private string m_bookAuthor;

    public BookComponent(string Title, string Author)
    {
        m_curISBNSite = null;
        Disposed = null;
        m_bookTitle = Title;
        m_bookAuthor = Author;
    }

    public string Title
    {
        get
        {
            return m_bookTitle;
        }
    }

    public string Author
    {
        get
        {
            return m_bookAuthor;
        }
    }

    public virtual void Dispose()
    {    
        //There is nothing to clean.
        if(Disposed != null)
            Disposed(this,EventArgs.Empty);
    }

    public virtual ISite Site
    {
        get
        {
            return m_curISBNSite;
        }
        set
        {
            m_curISBNSite = value;
        }
    }

    public override bool Equals(object cmp)
    {
        BookComponent cmpObj = (BookComponent)cmp;
        if(this.Title.Equals(cmpObj.Title) && this.Author.Equals(cmpObj.Author))
            return true;

        return false;
    }

    public override int GetHashCode()
    {
        return base.GetHashCode();
    }
}

/// <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
class ISBNSite implements ISite
{
    private IComponent mCurComponent;
    private IContainer mCurContainer;
    private boolean mbDesignMode;
    private String mISBNCmpName;

    public ISBNSite(IContainer actvCntr, IComponent prntCmpnt)
    {
        mCurComponent = prntCmpnt;
        mCurContainer = actvCntr;
        mbDesignMode = false;
        mISBNCmpName = null;
    } //ISBNSite

    //Support the ISite interface.
    /** @property 
     */
    public IComponent get_Component()
    {
        return mCurComponent;
    } //get_Component

    /** @property 
     */
    public IContainer get_Container()
    {
        return mCurContainer;
    } //get_Container

    /** @property 
     */
    public boolean get_DesignMode()
    {
        return mbDesignMode;
    } //get_DesignMode

    /** @property 
     */
    public String get_Name()
    {
        return mISBNCmpName;
    } //get_Name

    /** @property 
     */
    public void set_Name(String value)
    {
        mISBNCmpName = value;
    } //set_Name

    // Support the IServiceProvider interface.
    public Object GetService(Type serviceType)
    {
        // This example does not use any service object.
        return null;
    } //GetService
} //ISBNSite

// The BookComponent class represents the book component of the library 
// container. This class implements the IComponent interface.
class BookComponent implements IComponent
{
    public EventHandler disposed = null;

    /** @event 
     */
    public void add_Disposed(EventHandler p)
    {
        disposed = (EventHandler)System.Delegate.Combine(disposed, p);
    } //add_Disposed

    /** @event 
     */
    public void remove_Disposed(EventHandler p)
    {
        disposed = (EventHandler)System.Delegate.Remove(disposed, p);
    } //remove_Disposed

    private ISite mCurISBNSite;
    private String mBookTitle;
    private String mBookAuthor;

    public BookComponent(String title, String author)
    {
        mCurISBNSite = null;
        disposed = null;
        mBookTitle = title;
        mBookAuthor = author;
    } //BookComponent

    /** @property 
     */
    public String get_Title()
    {
        return mBookTitle;
    } //get_Title

    /** @property 
     */
    public String get_Author()
    {
        return mBookAuthor;
    } //get_Author

    public void Dispose()
    {
        // There is nothing to clean.
        if (disposed != null) {
            disposed.Invoke(this, EventArgs.Empty);
        }
    } //Dispose

    /** @property 
     */
    public ISite get_Site()
    {
        return mCurISBNSite;
    } //get_Site

    /** @property 
     */
    public void set_Site(ISite value)
    {
        mCurISBNSite = value;
    } //set_Site

    public boolean Equals(Object cmp)
    {
        BookComponent cmpObj = (BookComponent)cmp;
        if (this.get_Title().Equals(cmpObj.get_Title()) && this.get_Author().
                Equals(cmpObj.get_Author())) {
            return true;
        }
        return false;
    } //Equals

    public int GetHashCode()
    {
        return super.GetHashCode();
    } //GetHashCode
} //BookComponent

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0
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