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NameObjectCollectionBase.BaseGetAllKeys Method

Returns a String array that contains all the keys in the NameObjectCollectionBase instance.

Namespace:  System.Collections.Specialized
Assembly:  System (in System.dll)

protected string[] BaseGetAllKeys()

Return Value

Type: System.String[]
A String array that contains all the keys in the NameObjectCollectionBase instance.

This method is an O(n) operation, where n is Count.

The following code example uses BaseGetAllKeys and BaseGetAllValues to get an array of the keys or an array of the values.

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 );
      }
   }

   // 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 );
      }
   }

   // 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(System.String) ) );
      }
   }

}

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 );

      // Displays the list of keys.
      Console.WriteLine( "The list of keys:" );
      foreach ( String s in myCol.AllKeys )  {
         Console.WriteLine( "   {0}", s );
      }

      // Displays the list of values of type Object.
      Console.WriteLine( "The list of values (Object):" );
      foreach ( Object o in myCol.AllValues )  {
         Console.WriteLine( "   {0}", o.ToString() );
      }

      // Displays the list of values of type String.
      Console.WriteLine( "The list of values (String):" );
      foreach ( String s in myCol.AllValues )  {
         Console.WriteLine( "   {0}", s );
      }

   }

   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 list of keys:
   red
   yellow
   green
The list of values (Object):
   apple
   banana
   pear
The list of values (String):
   apple
   banana
   pear

*/

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

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