System.ComponentModel.IComponent Interface

Assembly: System.dll
Namespace: System.ComponentModel
Summary
Provides functionality required by all components. Component is the default implementation of IComponent and serves as the base class for all components in the common language runtime.
C# Syntax:
public interface IComponent : IDisposable
Remarks
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.

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 implementors: 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 the conceptual topic at MSDN: componentprogrammingessentials.
Example
	/// <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)
		{
			// we are not using any service objects in this example.
			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();
		}
	}

    
See also:
System.ComponentModel Namespace | Container | IContainer | ISite | Control

System.ComponentModel.IComponent Member List:

Public Properties
Site Read-write

Gets or sets the ISite associated with the IComponent.
Public Events
Disposed Represents the method that handles the IComponent.Disposed event of a component.

Hierarchy:


System.ComponentModel.IComponent Member Details

Property: Site (read-write)
Summary
Gets or sets the ISite associated with the IComponent.
C# Syntax:
ISite Site {get; set;}
Remarks
Sites can also serve as a repository for container-specific, per-component information, such as the component name.
See also:
ISite

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Event: Disposed
Summary
Represents the method that handles the IComponent.Disposed event of a component.
C# Syntax:
event EventHandler Disposed;
Remarks
When you create a IComponent delegate, you identify the method that handles the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see the conceptual topic at MSDN: eventsdelegates.
See also:
EventHandler

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