NameObjectCollectionBase.BaseGetAllKeys Method

Definition

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

C#
protected string[] BaseGetAllKeys();
C#
protected string?[] BaseGetAllKeys();

Returns

String[]

A String array that contains all the keys in the NameObjectCollectionBase instance.

Examples

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

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 );
      }
   }

   // 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

*/

Remarks

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

Applies to

Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1
UWP 10.0