NameObjectCollectionBase.BaseGetKey メソッド

.NET Framework クラス ライブラリ リファレンス

NameObjectCollectionBase.BaseGetKey メソッド

NameObjectCollectionBase インスタンスの指定したインデックスにあるエントリのキーを取得します。

名前空間: System.Collections.Specialized
アセンブリ: System (system.dll 内)
構文

Visual Basic (宣言)

Protected Function BaseGetKey ( _
    index As Integer _
) As String

Visual Basic (使用法)

Dim index As Integer
Dim returnValue As String

returnValue = Me.BaseGetKey(index)

C#

protected string BaseGetKey (
    int index
)

C++

protected:
String^ BaseGetKey (
    int index
)

J#

protected String BaseGetKey (
    int index
)

JScript

protected function BaseGetKey (
    index : int
) : String

パラメータ

index

取得するキーの 0 から始まるインデックス。

戻り値
指定したインデックスにあるエントリのキーを表す String。

例外

例外の種類	条件
ArgumentOutOfRangeException	index が、コレクションのインデックスの有効範囲外です。

解説

このメソッドは O(1) 操作です。

使用例

BaseGetKey および BaseGet を使用して、特定のキーと値を取得する方法については、次のコード例を参照してください。

Visual Basic

Imports System
Imports System.Collections
Imports System.Collections.Specialized

Public Class MyCollection
   Inherits NameObjectCollectionBase

   Private _de As New DictionaryEntry()

   ' Gets a key-and-value pair (DictionaryEntry) using an index.
   Default Public ReadOnly
 Property Item(index As Integer)
 As DictionaryEntry
      Get
         _de.Key = Me.BaseGetKey(index)
         _de.Value = Me.BaseGet(index)
         Return _de
      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

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

End Class 'MyCollection


Public Class SamplesNameObjectCollectionBase
   

   Public Shared Sub Main()

      ' Creates and initializes a new MyCollection instance.
      Dim d = New ListDictionary()
      d.Add("red", "apple")
      d.Add("yellow", "banana")
      d.Add("green", "pear")
      Dim myCol As New MyCollection(d)
      Console.WriteLine("Initial state of the collection (Count
 = {0}):", myCol.Count)
      PrintKeysAndValues(myCol)

      ' Gets specific keys and values.
      Console.WriteLine("The key at index 0 is {0}.",
 myCol(0).Key)
      Console.WriteLine("The value at index 0 is {0}.",
 myCol(0).Value)
      Console.WriteLine("The value associated with the key ""green""
 is {0}.", myCol("green"))

   End Sub 'Main

   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 'PrintKeysAndValues

End Class 'SamplesNameObjectCollectionBase
 


'This code produces the following output.
'
'Initial state of the collection (Count = 3):
'[0] : red, apple
'[1] : yellow, banana
'[2] : green, pear
'The key at index 0 is red.
'The value at index 0 is apple.
'The value associated with the key "green" is pear.

C#

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

public class MyCollection : NameObjectCollectionBase
  {

   private DictionaryEntry _de = new DictionaryEntry();

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

   // 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 );
      }
   }

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

}

public class SamplesNameObjectCollectionBase
  {

   public static void Main()
  {

      // Creates and initializes a new MyCollection instance.
      IDictionary d = new ListDictionary();
      d.Add( "red", "apple" );
      d.Add( "yellow", "banana" );
      d.Add( "green", "pear" );
      MyCollection myCol = new MyCollection( d );
      Console.WriteLine( "Initial state of the collection (Count = {0}):",
 myCol.Count );
      PrintKeysAndValues( myCol );

      // Gets specific keys and values.
      Console.WriteLine( "The key at index 0 is {0}.", myCol[0].Key );
      Console.WriteLine( "The value at index 0 is {0}.", myCol[0].Value
 );
      Console.WriteLine( "The value associated with the key \"green\"
 is {0}.", myCol["green"] );

   }

   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
 );
      }
   }

}


/*
This code produces the following output.

Initial state of the collection (Count = 3):
[0] : red, apple
[1] : yellow, banana
[2] : green, pear
The key at index 0 is red.
The value at index 0 is apple.
The value associated with the key "green" is pear.

*/

C++

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

public ref class MyCollection : public
 NameObjectCollectionBase  {

private:
   DictionaryEntry^ _de;

   // Gets a key-and-value pair (DictionaryEntry) using an index.
public:
   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 );
      }
   }

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

      _de = gcnew DictionaryEntry();

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

public ref class SamplesNameObjectCollectionBase
  {

public:
   static void Main()  {

      // Creates and initializes a new MyCollection instance.
      IDictionary^ d = gcnew ListDictionary();
      d->Add( "red", "apple" );
      d->Add( "yellow", "banana" );
      d->Add( "green", "pear" );
      MyCollection^ myCol = gcnew MyCollection( d );
      Console::WriteLine( "Initial state of the collection (Count = {0}):",
 myCol->Count );
      PrintKeysAndValues( myCol );

      // Gets specific keys and values.
      Console::WriteLine( "The key at index 0 is {0}.", myCol[0]->Key
 );
      Console::WriteLine( "The value at index 0 is {0}.", myCol[0]->Value
 );
      Console::WriteLine( "The value associated with the key \"green\"
 is {0}.", myCol["green"] );

   }

   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
 );
      }
   }
};

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

/*
This code produces the following output.

Initial state of the collection (Count = 3):
[0] : red, apple
[1] : yellow, banana
[2] : green, pear
The key at index 0 is red.
The value at index 0 is apple.
The value associated with the key "green" is pear.

*/

J#

import System.* ;
import System.Collections.* ;
import System.Collections.Specialized.* ;

public class MyCollection extends NameObjectCollectionBase
{   
    private DictionaryEntry _de =  new DictionaryEntry();

    // Gets a key-and-value pair (DictionaryEntry) using an index.
    /** @property 
     */
    public DictionaryEntry get_Item(int index)
    {
        _de.set_Key(this.BaseGetKey(index));
        _de.set_Value(this.BaseGet(index));
        return _de ;
    } //get_Item

    // Gets or sets the value associated with the specified key.
    /** @property 
     */
    public Object get_Item(String key)
    {
        return this.BaseGet(key) ;
    } //get_Item

    /** @property 
     */
    public void set_Item(String key,Object
 value )
    {
        this.BaseSet(key, value);
    } //set_Item

    //default constructor
    public MyCollection() 
    { 
    } //MyCollection

    // Adds elements from an IDictionary into the new collection.
    public MyCollection(IDictionary d)
    {

        IDictionaryEnumerator objEnum = d.GetEnumerator();

        while(objEnum.MoveNext()) {
            DictionaryEntry de = (DictionaryEntry)objEnum.get_Current();
            this.BaseAdd(((String)(de.get_Key())), de.get_Value());
        }
    } //MyCollection
} //MyCollection

 
public class SamplesNameObjectCollectionBase
{
    public static void main(String[]
 args)
    {
        // Creates and initializes a new MyCollection instance.
        IDictionary d = new ListDictionary();
        d.Add("red", "apple");
        d.Add("yellow", "banana");
        d.Add("green", "pear");
        MyCollection myCol =  new MyCollection(d);
        Console.WriteLine("Initial state of the collection (Count = {0}):"
,
            System.Convert.ToString(myCol.get_Count()));
        PrintKeysAndValues(myCol);

        // Gets specific keys and values.
        Console.WriteLine("The key at index 0 is {0}.",
            myCol.get_Item( 0).get_Key());
        Console.WriteLine("The value at index 0 is {0}.", 
            myCol.get_Item( 0).get_Value());
        Console.WriteLine("The value associated with the key \"green\"
 is {0}.",
            myCol.get_Item( "green"));
    } //main

    public static void PrintKeysAndValues(MyCollection
 myCol)
    {
        for (int i=0 ; i < myCol.get_Count();
 i++) {
            Console.WriteLine("[{0}] : {1}, {2}", System.Convert.ToString(i)
,
                myCol.get_Item(i).get_Key(), myCol.get_Item(i).get_Value());
        } 
    } //PrintKeysAndValues
} //SamplesNameObjectCollectionBase

/*
This code produces the following output.

Initial state of the collection (Count = 3):
[0] : red, apple
[1] : yellow, banana
[2] : green, pear
The key at index 0 is red.
The value at index 0 is apple.
The value associated with the key "green" is pear.

*/

プラットフォーム

Windows 98, Windows 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

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0
.NET Compact Framework
サポート対象 : 2.0、1.0

参照

関連項目
NameObjectCollectionBase クラス
NameObjectCollectionBase メンバ
System.Collections.Specialized 名前空間