NameObjectCollectionBase 類別

定義

命名空間:

System.Collections.Specialized

組件:

System.Collections.Specialized.dll

來源:

NameObjectCollectionBase.cs

提供 abstract 基底類別給可以用索引鍵或索引來存取之相關聯的 String 索引鍵和 Object 值集合。

public ref class NameObjectCollectionBase abstract : System::Collections::ICollection, System::Runtime::Serialization::IDeserializationCallback, System::Runtime::Serialization::ISerializable

public abstract class NameObjectCollectionBase : System.Collections.ICollection, System.Runtime.Serialization.IDeserializationCallback, System.Runtime.Serialization.ISerializable

type NameObjectCollectionBase = class
    interface ICollection
    interface IEnumerable
    interface IDeserializationCallback
    interface ISerializable

Public MustInherit Class NameObjectCollectionBase
Implements ICollection, IDeserializationCallback, ISerializable

繼承

Object

NameObjectCollectionBase

衍生

System.Collections.Specialized.NameValueCollection

System.Configuration.ConfigurationSectionCollection

System.Configuration.ConfigurationSectionGroupCollection

System.Configuration.PropertyInformationCollection

System.Management.ManagementNamedValueCollection

System.Web.Configuration.VirtualDirectoryMappingCollection

System.Web.HttpApplicationState

System.Web.HttpApplicationStateBase

System.Web.HttpCookieCollection

System.Web.HttpFileCollection

System.Web.HttpFileCollectionBase

System.Web.HttpModuleCollection

System.Web.SessionState.SessionStateItemCollection

實作

ICollection IEnumerable IDeserializationCallback ISerializable

範例

下列程式代碼範例示範如何實作 NameObjectCollectionBase 和使用 類別。

#using <System.dll>
using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;

public ref class MyCollection : public NameObjectCollectionBase  {

private:
   DictionaryEntry^ _de;

   // Creates an empty collection.
public:
   MyCollection()  {
      _de = gcnew DictionaryEntry();
   }

   // Adds elements from an IDictionary into the new collection.
   MyCollection( IDictionary^ d, Boolean bReadOnly )  {

      _de = gcnew DictionaryEntry();

      for each ( DictionaryEntry^ de in d )  {
         this->BaseAdd( (String^) de->Key, de->Value );
      }
      this->IsReadOnly = bReadOnly;
   }

   // Gets a key-and-value pair (DictionaryEntry) using an index.
   property DictionaryEntry^ default[ int ]  {
      DictionaryEntry^ get(int index)  {
         _de->Key = this->BaseGetKey(index);
         _de->Value = this->BaseGet(index);
         return( _de );
      }
   }

   // Gets or sets the value associated with the specified key.
   property Object^ default[ String^ ]  {
      Object^ get(String^ key)  {
         return( this->BaseGet( key ) );
      }
      void set( String^ key, Object^ value )  {
         this->BaseSet( key, value );
      }
   }

   // Gets a String array that contains all the keys in the collection.
   property array<String^>^ AllKeys  {
      array<String^>^ get()  {
         return( (array<String^>^)this->BaseGetAllKeys() );
      }
   }

   // Gets an Object array that contains all the values in the collection.
   property Array^ AllValues  {
      Array^ get()  {
         return( this->BaseGetAllValues() );
      }
   }

   // Gets a String array that contains all the values in the collection.
   property array<String^>^ AllStringValues  {
      array<String^>^ get()  {
         return( (array<String^>^) this->BaseGetAllValues(  String ::typeid ));
      }
   }

   // Gets a value indicating if the collection contains keys that are not null.
   property Boolean HasKeys  {
      Boolean get()  {
         return( this->BaseHasKeys() );
      }
   }

   // Adds an entry to the collection.
   void Add( String^ key, Object^ value )  {
      this->BaseAdd( key, value );
   }

   // Removes an entry with the specified key from the collection.
   void Remove( String^ key )  {
      this->BaseRemove( key );
   }

   // Removes an entry in the specified index from the collection.
   void Remove( int index )  {
      this->BaseRemoveAt( index );
   }

   // Clears all the elements in the collection.
   void Clear()  {
      this->BaseClear();
   }
};

public ref class SamplesNameObjectCollectionBase  {

public:
   static void Main()  {
      // Creates and initializes a new MyCollection that is read-only.
      IDictionary^ d = gcnew ListDictionary();
      d->Add( "red", "apple" );
      d->Add( "yellow", "banana" );
      d->Add( "green", "pear" );
      MyCollection^ myROCol = gcnew MyCollection( d, true );

      // Tries to add a new item.
      try  {
         myROCol->Add( "blue", "sky" );
      }
      catch ( NotSupportedException^ e )  {
         Console::WriteLine( e->ToString() );
      }

      // Displays the keys and values of the MyCollection.
      Console::WriteLine( "Read-Only Collection:" );
      PrintKeysAndValues( myROCol );

      // Creates and initializes an empty MyCollection that is writable.
      MyCollection^ myRWCol = gcnew MyCollection();

      // Adds new items to the collection.
      myRWCol->Add( "purple", "grape" );
      myRWCol->Add( "orange", "tangerine" );
      myRWCol->Add( "black", "berries" );
      Console::WriteLine( "Writable Collection (after adding values):" );
      PrintKeysAndValues( myRWCol );

      // Changes the value of one element.
      myRWCol["orange"] = "grapefruit";
      Console::WriteLine( "Writable Collection (after changing one value):" );
      PrintKeysAndValues( myRWCol );

      // Removes one item from the collection.
      myRWCol->Remove( "black" );
      Console::WriteLine( "Writable Collection (after removing one value):" );
      PrintKeysAndValues( myRWCol );

      // Removes all elements from the collection.
      myRWCol->Clear();
      Console::WriteLine( "Writable Collection (after clearing the collection):" );
      PrintKeysAndValues( myRWCol );
   }

   // Prints the indexes, keys, and values.
   static void PrintKeysAndValues( MyCollection^ myCol )  {
      for ( int i = 0; i < myCol->Count; i++ )  {
         Console::WriteLine( "[{0}] : {1}, {2}", i, myCol[i]->Key, myCol[i]->Value );
      }
   }

   // Prints the keys and values using AllKeys.
   static void PrintKeysAndValues2( MyCollection^ myCol )  {
      for each ( String^ s in myCol->AllKeys )  {
         Console::WriteLine( "{0}, {1}", s, myCol[s] );
      }
   }
};

int main()
{
    SamplesNameObjectCollectionBase::Main();
}

/*
This code produces the following output.

System.NotSupportedException: Collection is read-only.
   at System.Collections.Specialized.NameObjectCollectionBase.BaseAdd(String name, Object value)
   at SamplesNameObjectCollectionBase.Main()
Read-Only Collection:
[0] : red, apple
[1] : yellow, banana
[2] : green, pear
Writable Collection (after adding values):
[0] : purple, grape
[1] : orange, tangerine
[2] : black, berries
Writable Collection (after changing one value):
[0] : purple, grape
[1] : orange, grapefruit
[2] : black, berries
Writable Collection (after removing one value):
[0] : purple, grape
[1] : orange, grapefruit
Writable Collection (after clearing the collection):

*/

using System;
using System.Collections;
using System.Collections.Specialized;

public class MyCollection : NameObjectCollectionBase
{
   // Creates an empty collection.
   public MyCollection()  {
   }

   // Adds elements from an IDictionary into the new collection.
   public MyCollection( IDictionary d, Boolean bReadOnly )  {
      foreach ( DictionaryEntry de in d )  {
         this.BaseAdd( (String) de.Key, de.Value );
      }
      this.IsReadOnly = bReadOnly;
   }

   // Gets a key-and-value pair (DictionaryEntry) using an index.
   public DictionaryEntry this[ int index ]  {
      get  {
          return ( new DictionaryEntry(
              this.BaseGetKey(index), this.BaseGet(index) ) );
      }
   }

   // Gets or sets the value associated with the specified key.
   public Object this[ String key ]  {
      get  {
         return( this.BaseGet( key ) );
      }
      set  {
         this.BaseSet( key, value );
      }
   }

   // Gets a String array that contains all the keys in the collection.
   public String[] AllKeys  {
      get  {
         return( this.BaseGetAllKeys() );
      }
   }

   // Gets an Object array that contains all the values in the collection.
   public Array AllValues  {
      get  {
         return( this.BaseGetAllValues() );
      }
   }

   // Gets a String array that contains all the values in the collection.
   public String[] AllStringValues  {
      get  {
         return( (String[]) this.BaseGetAllValues( typeof( string ) ));
      }
   }

   // Gets a value indicating if the collection contains keys that are not null.
   public Boolean HasKeys  {
      get  {
         return( this.BaseHasKeys() );
      }
   }

   // Adds an entry to the collection.
   public void Add( String key, Object value )  {
      this.BaseAdd( key, value );
   }

   // Removes an entry with the specified key from the collection.
   public void Remove( String key )  {
      this.BaseRemove( key );
   }

   // Removes an entry in the specified index from the collection.
   public void Remove( int index )  {
      this.BaseRemoveAt( index );
   }

   // Clears all the elements in the collection.
   public void Clear()  {
      this.BaseClear();
   }
}

public class SamplesNameObjectCollectionBase  {

   public static void Main()  {

      // Creates and initializes a new MyCollection that is read-only.
      IDictionary d = new ListDictionary();
      d.Add( "red", "apple" );
      d.Add( "yellow", "banana" );
      d.Add( "green", "pear" );
      MyCollection myROCol = new MyCollection( d, true );

      // Tries to add a new item.
      try  {
         myROCol.Add( "blue", "sky" );
      }
      catch ( NotSupportedException e )  {
         Console.WriteLine( e.ToString() );
      }

      // Displays the keys and values of the MyCollection.
      Console.WriteLine( "Read-Only Collection:" );
      PrintKeysAndValues( myROCol );

      // Creates and initializes an empty MyCollection that is writable.
      MyCollection myRWCol = new MyCollection();

      // Adds new items to the collection.
      myRWCol.Add( "purple", "grape" );
      myRWCol.Add( "orange", "tangerine" );
      myRWCol.Add( "black", "berries" );
      Console.WriteLine( "Writable Collection (after adding values):" );
      PrintKeysAndValues( myRWCol );

      // Changes the value of one element.
      myRWCol["orange"] = "grapefruit";
      Console.WriteLine( "Writable Collection (after changing one value):" );
      PrintKeysAndValues( myRWCol );

      // Removes one item from the collection.
      myRWCol.Remove( "black" );
      Console.WriteLine( "Writable Collection (after removing one value):" );
      PrintKeysAndValues( myRWCol );

      // Removes all elements from the collection.
      myRWCol.Clear();
      Console.WriteLine( "Writable Collection (after clearing the collection):" );
      PrintKeysAndValues( myRWCol );
   }

   // Prints the indexes, keys, and values.
   public static void PrintKeysAndValues( MyCollection myCol )  {
      for ( int i = 0; i < myCol.Count; i++ )  {
         Console.WriteLine( "[{0}] : {1}, {2}", i, myCol[i].Key, myCol[i].Value );
      }
   }

   // Prints the keys and values using AllKeys.
   public static void PrintKeysAndValues2( MyCollection myCol )  {
      foreach ( String s in myCol.AllKeys )  {
         Console.WriteLine( "{0}, {1}", s, myCol[s] );
      }
   }
}


/*
This code produces the following output.

System.NotSupportedException: Collection is read-only.
   at System.Collections.Specialized.NameObjectCollectionBase.BaseAdd(String name, Object value)
   at SamplesNameObjectCollectionBase.Main()
Read-Only Collection:
[0] : red, apple
[1] : yellow, banana
[2] : green, pear
Writable Collection (after adding values):
[0] : purple, grape
[1] : orange, tangerine
[2] : black, berries
Writable Collection (after changing one value):
[0] : purple, grape
[1] : orange, grapefruit
[2] : black, berries
Writable Collection (after removing one value):
[0] : purple, grape
[1] : orange, grapefruit
Writable Collection (after clearing the collection):

*/

Imports System.Collections
Imports System.Collections.Specialized

Public Class MyCollection
   Inherits NameObjectCollectionBase

   ' Creates an empty collection.
   Public Sub New()
   End Sub

   ' Adds elements from an IDictionary into the new collection.
   Public Sub New(d As IDictionary, bReadOnly As Boolean)
      Dim de As DictionaryEntry
      For Each de In  d
         Me.BaseAdd(CType(de.Key, String), de.Value)
      Next de
      Me.IsReadOnly = bReadOnly
   End Sub

   ' Gets a key-and-value pair (DictionaryEntry) using an index.
   Default Public ReadOnly Property Item(index As Integer) As DictionaryEntry
      Get
            return new DictionaryEntry( _
                me.BaseGetKey(index), me.BaseGet(index) )
      End Get
   End Property

   ' Gets or sets the value associated with the specified key.
   Default Public Property Item(key As String) As Object
      Get
         Return Me.BaseGet(key)
      End Get
      Set
         Me.BaseSet(key, value)
      End Set
   End Property

   ' Gets a String array that contains all the keys in the collection.
   Public ReadOnly Property AllKeys() As String()
      Get
         Return Me.BaseGetAllKeys()
      End Get
   End Property

   ' Gets an Object array that contains all the values in the collection.
   Public ReadOnly Property AllValues() As Array
      Get
         Return Me.BaseGetAllValues()
      End Get
   End Property

   ' Gets a String array that contains all the values in the collection.
   Public ReadOnly Property AllStringValues() As String()
      Get
         Return CType(Me.BaseGetAllValues(GetType(String)), String())
      End Get
   End Property

   ' Gets a value indicating if the collection contains keys that are not null.
   Public ReadOnly Property HasKeys() As Boolean
      Get
         Return Me.BaseHasKeys()
      End Get
   End Property

   ' Adds an entry to the collection.
   Public Sub Add(key As String, value As Object)
      Me.BaseAdd(key, value)
   End Sub

   ' Removes an entry with the specified key from the collection.
   Overloads Public Sub Remove(key As String)
      Me.BaseRemove(key)
   End Sub

   ' Removes an entry in the specified index from the collection.
   Overloads Public Sub Remove(index As Integer)
      Me.BaseRemoveAt(index)
   End Sub

   ' Clears all the elements in the collection.
   Public Sub Clear()
      Me.BaseClear()
   End Sub

End Class


Public Class SamplesNameObjectCollectionBase   

   Public Shared Sub Main()

      ' Creates and initializes a new MyCollection that is read-only.
      Dim d As New ListDictionary()
      d.Add("red", "apple")
      d.Add("yellow", "banana")
      d.Add("green", "pear")
      Dim myROCol As New MyCollection(d, True)

      ' Tries to add a new item.
      Try
         myROCol.Add("blue", "sky")
      Catch e As NotSupportedException
         Console.WriteLine(e.ToString())
      End Try

      ' Displays the keys and values of the MyCollection.
      Console.WriteLine("Read-Only Collection:")
      PrintKeysAndValues(myROCol)

      ' Creates and initializes an empty MyCollection that is writable.
      Dim myRWCol As New MyCollection()

      ' Adds new items to the collection.
      myRWCol.Add("purple", "grape")
      myRWCol.Add("orange", "tangerine")
      myRWCol.Add("black", "berries")
      Console.WriteLine("Writable Collection (after adding values):")
      PrintKeysAndValues(myRWCol)

      ' Changes the value of one element.
      myRWCol("orange") = "grapefruit"
      Console.WriteLine("Writable Collection (after changing one value):")
      PrintKeysAndValues(myRWCol)

      ' Removes one item from the collection.
      myRWCol.Remove("black")
      Console.WriteLine("Writable Collection (after removing one value):")
      PrintKeysAndValues(myRWCol)

      ' Removes all elements from the collection.
      myRWCol.Clear()
      Console.WriteLine("Writable Collection (after clearing the collection):")
      PrintKeysAndValues(myRWCol)

   End Sub

   ' Prints the indexes, keys, and values.
   Public Shared Sub PrintKeysAndValues(myCol As MyCollection)
      Dim i As Integer
      For i = 0 To myCol.Count - 1
         Console.WriteLine("[{0}] : {1}, {2}", i, myCol(i).Key, myCol(i).Value)
      Next i
   End Sub

   ' Prints the keys and values using AllKeys.
   Public Shared Sub PrintKeysAndValues2(myCol As MyCollection)
      Dim s As String
      For Each s In  myCol.AllKeys
         Console.WriteLine("{0}, {1}", s, myCol(s))
      Next s
   End Sub

End Class


'This code produces the following output.
'
'System.NotSupportedException: Collection is read-only.
'   at System.Collections.Specialized.NameObjectCollectionBase.BaseAdd(String name, Object value)
'   at SamplesNameObjectCollectionBase.Main()
'Read-Only Collection:
'[0] : red, apple
'[1] : yellow, banana
'[2] : green, pear
'Writable Collection (after adding values):
'[0] : purple, grape
'[1] : orange, tangerine
'[2] : black, berries
'Writable Collection (after changing one value):
'[0] : purple, grape
'[1] : orange, grapefruit
'[2] : black, berries
'Writable Collection (after removing one value):
'[0] : purple, grape
'[1] : orange, grapefruit
'Writable Collection (after clearing the collection):

備註

這個類別的基礎結構是哈希表。

每個元素都是索引鍵/值組。

的 NameObjectCollectionBase 容量是 可以保留的項目 NameObjectCollectionBase 數目。 隨著元素新增至 NameObjectCollectionBase，容量會隨著重新配置而自動增加。

哈希碼提供者會為 實例中的 NameObjectCollectionBase 索引鍵分配哈希碼。 預設哈希碼提供者為 CaseInsensitiveHashCodeProvider。

比較子會判斷兩個索引鍵是否相等。 預設比較子是 CaseInsensitiveComparer。

在 .NET Framework 1.0 版中，此類別會使用區分文化特性的字串比較。 不過，在 .NET Framework 1.1 版和更新版本中，此類別會在比較字串時使用 CultureInfo.InvariantCulture 。 如需文化特性如何影響比較和排序的詳細資訊，請參閱 執行 Culture-Insensitive 字串作業。

null 允許做為索引鍵或值。

警告

因為BaseGet找不到指定的索引鍵，而且null因為與索引鍵相關聯的值是 null，所以方法不會區分null傳回的 。

建構函式

NameObjectCollectionBase()	初始化 NameObjectCollectionBase 類別的新執行個體，這個執行個體是空白的。
NameObjectCollectionBase(IEqualityComparer)	初始化 NameObjectCollectionBase 類別的新執行個體，這個執行個體是空白的、具有預設的初始容量，並使用指定的 IEqualityComparer 物件。
NameObjectCollectionBase(IHashCodeProvider, IComparer)	已淘汰. 初始化 NameObjectCollectionBase 類別的新執行個體，這個執行個體是空白的、具有預設的初始容量，並使用指定的雜湊碼提供者和指定的比較子。
NameObjectCollectionBase(Int32)	初始化 NameObjectCollectionBase 類別的新執行個體，這個執行個體是空白的、具有指定的初始容量，並使用預設雜湊碼提供者和預設比較子。
NameObjectCollectionBase(Int32, IEqualityComparer)	初始化 NameObjectCollectionBase 類別的新執行個體，這個執行個體是空白的、具有指定的初始容量，並使用指定的 IEqualityComparer 物件。
NameObjectCollectionBase(Int32, IHashCodeProvider, IComparer)	已淘汰. 初始化 NameObjectCollectionBase 類別的新執行個體，這個執行個體是空白的、具有指定的初始容量，並使用指定的雜湊碼提供者和指定的比較子。
NameObjectCollectionBase(SerializationInfo, StreamingContext)	已淘汰. 初始化 NameObjectCollectionBase 類別的新執行個體，這個執行個體可序列化，並使用指定的 SerializationInfo 和 StreamingContext。

屬性

Count	取得 NameObjectCollectionBase 執行個體中包含的索引鍵/值組數目。
IsReadOnly	取得或設定值，表示 NameObjectCollectionBase 執行個體是否為唯讀。
Keys	取得 NameObjectCollectionBase.KeysCollection 執行個體，其中包含 NameObjectCollectionBase 執行個體內的所有索引鍵。

方法

BaseAdd(String, Object)	將具有指定索引鍵和值的項目加入 NameObjectCollectionBase 執行個體。
BaseClear()	將所有項目從 NameObjectCollectionBase 執行個體中移除。
BaseGet(Int32)	取得 NameObjectCollectionBase 執行個體指定索引處之項目的值。
BaseGet(String)	從 NameObjectCollectionBase 執行個體取得具有指定索引鍵之第一個項目的值。
BaseGetAllKeys()	傳回 String 陣列，其中包含 NameObjectCollectionBase 執行個體中的所有索引鍵。
BaseGetAllValues()	傳回 Object 陣列，其中包含 NameObjectCollectionBase 執行個體中的所有值。
BaseGetAllValues(Type)	傳回指定類型的陣列，其中包含 NameObjectCollectionBase 執行個體中的所有值。
BaseGetKey(Int32)	取得 NameObjectCollectionBase 執行個體指定索引處之項目的索引鍵。
BaseHasKeys()	取得值，表示 NameObjectCollectionBase 執行個體是否包含其索引鍵不是 null 的項目。
BaseRemove(String)	將具有指定索引鍵的項目從 NameObjectCollectionBase 中移除。
BaseRemoveAt(Int32)	移除 NameObjectCollectionBase 執行個體指定索引處的項目。
BaseSet(Int32, Object)	設定 NameObjectCollectionBase 執行個體指定索引處之項目的值。
BaseSet(String, Object)	設定 NameObjectCollectionBase 執行個體中具有指定索引鍵之第一個項目的值 (如果有找到)，否則將具有指定索引鍵和值的項目加入 NameObjectCollectionBase 執行個體。
Equals(Object)	判斷指定的物件是否等於目前的物件。 (繼承來源 Object)
GetEnumerator()	傳回在 NameObjectCollectionBase 中逐一查看的列舉值。
GetHashCode()	做為預設雜湊函式。 (繼承來源 Object)
GetObjectData(SerializationInfo, StreamingContext)	已淘汰. 實作 ISerializable 介面，並傳回序列化 NameObjectCollectionBase 執行個體所需的資料。
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)
OnDeserialization(Object)	實作 ISerializable 介面，並於還原序列化完成時引發還原序列化事件。
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 NameObjectCollectionBase 複製到相容的一維 Array。
ICollection.IsSynchronized	取得值，表示是否要同步處理 (執行緒安全) 對 NameObjectCollectionBase 物件的存取。
ICollection.SyncRoot	取得可用來同步處理對 NameObjectCollectionBase 物件之存取的物件。

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。

執行緒安全性

Visual Basic 中的公用靜態 (Shared) 此類型的成員是安全線程。 並非所有的執行個體成員都是安全執行緒。

這個實作不提供的同步處理 (線程安全) 包裝NameObjectCollectionBase函式，但衍生類別可以使用 屬性建立自己的同步版本NameObjectCollectionBaseSyncRoot。

透過集合列舉本質上不是安全線程程式。 即使集合經過同步化，其他的執行緒仍可修改該集合，使列舉值擲回例外狀況。 若要保證列舉過程的執行緒安全，您可以在整個列舉過程中鎖定集合，或攔截由其他執行緒的變更所造成的例外狀況。

另請參閱

• Hashtable
• NameValueCollection
• String
• 執行不區分文化特性的字串作業