ComponentCollection 類別

定義

命名空間:

System.ComponentModel

組件:

System.ComponentModel.Primitives.dll

來源:

ComponentCollection.cs

提供 IComponent 物件集合的唯讀容器。

public ref class ComponentCollection : System::Collections::ReadOnlyCollectionBase

public class ComponentCollection : System.Collections.ReadOnlyCollectionBase

type ComponentCollection = class
    inherit ReadOnlyCollectionBase

Public Class ComponentCollection
Inherits ReadOnlyCollectionBase

繼承

Object

ReadOnlyCollectionBase

ComponentCollection

範例

下列程式代碼範例示範如何使用 ComponentCollection 來列舉自定義 BookComponent 物件的集合。

//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.

class LibraryContainer : IContainer
{
    private ArrayList m_bookList;

    public LibraryContainer()
    {
        m_bookList = new ArrayList();
    }

    public virtual void Add(IComponent book)
    {
        //The book will be added without creation of the ISite object.
        m_bookList.Add(book);
    }

    public virtual void Add(IComponent book, string ISNDNNum)
    {
        for(int i =0; i < m_bookList.Count; ++i)
        {
            IComponent curObj = (IComponent)m_bookList[i];
            if(curObj.Site != null)
            {
                if(curObj.Site.Name.Equals(ISNDNNum))
                    throw new ArgumentException("The ISBN number already exists in the container"); 
            }
        }

        ISBNSite data = new ISBNSite(this, book);
        data.Name = ISNDNNum;
        book.Site = data;
        m_bookList.Add(book);
    }

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

    public ComponentCollection Components
    {
        get
        {
            IComponent[] datalist = new BookComponent[m_bookList.Count];
            m_bookList.CopyTo(datalist);
            return new ComponentCollection(datalist);
        }
    }

    public virtual void Dispose()
    {	
        for(int i =0; i < m_bookList.Count; ++i)
        {
            IComponent curObj = (IComponent)m_bookList[i];
            curObj.Dispose();
        }
        
        m_bookList.Clear();
    }

    static void Main(string[] args)
    {
        LibraryContainer cntrExmpl = new LibraryContainer();

        try 
        {
            BookComponent book1 = new BookComponent("Wizard's First Rule", "Terry Gooodkind");
            cntrExmpl.Add(book1, "0812548051");
            BookComponent book2 = new BookComponent("Stone of Tears", "Terry Gooodkind");
            cntrExmpl.Add(book2, "0812548094");
            BookComponent book3 = new BookComponent("Blood of the Fold", "Terry Gooodkind");
            cntrExmpl.Add(book3, "0812551478");
            BookComponent book4 = new 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 (ArgumentException e)
        {
            Console.WriteLine("Unable to add books: " + e.Message);
        }

        ComponentCollection datalist =cntrExmpl.Components;
        IEnumerator denum = datalist.GetEnumerator();

        while(denum.MoveNext())
        {
            BookComponent cmp = (BookComponent)denum.Current;
            Console.WriteLine("Book Title: " + cmp.Title);
            Console.WriteLine("Book Author: " + cmp.Author);
            Console.WriteLine("Book ISBN: " + cmp.Site.Name);
        }
    }
}

    '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.

Class LibraryContainer
    Implements IContainer
    Private m_bookList As ArrayList

    Public Sub New()
        m_bookList = New ArrayList()
    End Sub

    Public Sub Add(ByVal book As IComponent) Implements IContainer.Add
        'The book will be added without creation of the ISite object.
        m_bookList.Add(book)
    End Sub

    Public Sub Add(ByVal book As IComponent, ByVal ISNDNNum As String) Implements IContainer.Add

        Dim i As Integer
        Dim curObj As IComponent

        For i = 0 To m_bookList.Count - 1
            curObj = CType(m_bookList(i), IComponent)
            If curObj.Site IsNot Nothing Then
                If (curObj.Site.Name.Equals(ISNDNNum)) Then
                    Throw New ArgumentException("The ISBN number already exists in the container")
                End If
            End If
        Next i

        Dim data As ISBNSite = New ISBNSite(Me, book)
        data.Name = ISNDNNum
        book.Site = data
        m_bookList.Add(book)

    End Sub

    Public Sub Remove(ByVal book As IComponent) Implements IContainer.Remove
        Dim i As Integer
        Dim curComp As BookComponent = CType(book, BookComponent)

        For i = 0 To m_bookList.Count - 1
            If (curComp.Equals(m_bookList(i)) = True) Then
                m_bookList.RemoveAt(i)
                Exit For
            End If
        Next i
    End Sub


    Public ReadOnly Property Components() As ComponentCollection Implements IContainer.Components
        Get
            Dim datalist(m_bookList.Count - 1) As IComponent
            
            m_bookList.CopyTo(datalist)
            Return New ComponentCollection(datalist)
        End Get
    End Property

    Public Overridable Sub Dispose() Implements IDisposable.Dispose
        Dim i As Integer
        For i = 0 To m_bookList.Count - 1
            Dim curObj As IComponent = CType(m_bookList(i), IComponent)
            curObj.Dispose()
        Next i

        m_bookList.Clear()
    End Sub

    Public Shared Sub Main()
        Dim cntrExmpl As LibraryContainer = New LibraryContainer()

        Try
            Dim book1 As BookComponent = New BookComponent("Wizard's First Rule", "Terry Gooodkind")
            cntrExmpl.Add(book1, "0812548051")
            Dim book2 As BookComponent = New BookComponent("Stone of Tears", "Terry Gooodkind")
            cntrExmpl.Add(book2, "0812548094")
            Dim book3 As BookComponent = New BookComponent("Blood of the Fold", "Terry Gooodkind")
            cntrExmpl.Add(book3, "0812551478")
            Dim book4 As BookComponent = New BookComponent("The Soul of the Fire", "Terry Gooodkind")
            'This will generate an exception, because the ISBN already exists in the container.
            cntrExmpl.Add(book4, "0812551478")
        Catch e As ArgumentException
            Console.WriteLine("Unable to add books: " + e.Message)
        End Try

        Dim datalist As ComponentCollection = cntrExmpl.Components
        Dim denum As IEnumerator = datalist.GetEnumerator()

        While (denum.MoveNext())
            Dim cmp As BookComponent = CType(denum.Current, BookComponent)
            Console.WriteLine("Book Title: " + cmp.Title)
            Console.WriteLine("Book Author: " + cmp.Author)
            Console.WriteLine("Book ISBN: " + cmp.Site.Name)
        End While
    End Sub
End Class

備註

這個集合繼承自 ReadOnlyCollectionBase。 將物件新增 IComponent 至這個集合的唯一方法是使用類別建構函式。

此集合提供兩個索引器屬性：字串索引器和整數索引器。 如果 Site 集合中的元件屬性不是 null ，而且 Name 元件的 屬性 Site 符合指定的字串，則字串索引器屬性會依名稱傳回集合中的元件。 整數索引器屬性會在 IComponent 指定的集合索引處傳回 。 方法 CopyTo 會將集合的內容複製到指定的陣列，開始寫入指定索引處的陣列。

建構函式

ComponentCollection(IComponent[])

使用指定的元件陣列，初始化 ComponentCollection 類別的新執行個體。

屬性

Count	取得 ReadOnlyCollectionBase 執行個體中包含的元素數目。 (繼承來源 ReadOnlyCollectionBase)
InnerList	取得包含於 ReadOnlyCollectionBase 執行個體中的項目清單。 (繼承來源 ReadOnlyCollectionBase)
Item[Int32]	取得集合中指定集合索引上的 Component。
Item[String]	取得集合中符合指定名稱的所有元件。

方法

CopyTo(IComponent[], Int32)	將整個集合複製至陣列，並於指定的陣列索引處開始寫入。
Equals(Object)	判斷指定的物件是否等於目前的物件。 (繼承來源 Object)
GetEnumerator()	傳回可逐一查看 ReadOnlyCollectionBase 執行個體的列舉值。 (繼承來源 ReadOnlyCollectionBase)
GetHashCode()	做為預設雜湊函式。 (繼承來源 Object)
GetType()	取得目前執行個體的 Type。 (繼承來源 Object)
MemberwiseClone()	建立目前 Object 的淺層複製。 (繼承來源 Object)
ToString()	傳回代表目前物件的字串。 (繼承來源 Object)

明確介面實作

ICollection.CopyTo(Array, Int32)	從目標陣列的指定索引開始，將整個 ReadOnlyCollectionBase 複製到相容的一維 Array。 (繼承來源 ReadOnlyCollectionBase)
ICollection.IsSynchronized	取得值，指出對 ReadOnlyCollectionBase 物件的存取是否為同步的 (執行緒安全)。 (繼承來源 ReadOnlyCollectionBase)
ICollection.SyncRoot	取得可用來同步存取 ReadOnlyCollectionBase 物件的物件。 (繼承來源 ReadOnlyCollectionBase)

擴充方法

Cast<TResult>(IEnumerable)	將 IEnumerable 的項目轉換成指定的型別。
OfType<TResult>(IEnumerable)	根據指定的型別來篩選 IEnumerable 的項目。
AsParallel(IEnumerable)	啟用查詢的平行化作業。
AsQueryable(IEnumerable)	將 IEnumerable 轉換成 IQueryable。

另請參閱

• IComponent