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NameObjectCollectionBase.BaseRemove Method

Removes the entries with the specified key from the NameObjectCollectionBase instance.

[Visual Basic]
Protected Sub BaseRemove( _
   ByVal name As String _
)
[C#]
protected void BaseRemove(
 string name
);
[C++]
protected: void BaseRemove(
 String* name
);
[JScript]
protected function BaseRemove(
   name : String
);

Parameters

name
The String key of the entries to remove. The key can be a null reference (Nothing in Visual Basic).

Exceptions

Exception Type Condition
NotSupportedException The collection is read-only.

-or-

The collection has a fixed size.

Remarks

In collections of contiguous elements, such as lists, the elements that follow the removed element move up to occupy the vacated spot. If the collection is indexed, the indexes of the elements that are moved are also updated. This behavior does not apply to collections where elements are conceptually grouped into buckets, such as a hashtable.

Example

[Visual Basic, C#, C++] The following code example uses BaseRemove and BaseRemoveAt to remove elements from a NameObjectCollectionBase.

[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

   ' 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

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

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

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)

      ' Removes an element at a specific index.
      myCol.Remove(1)
      Console.WriteLine("After removing the element at index 1 (Count = {0}):", myCol.Count)
      PrintKeysAndValues(myCol)

      ' Removes an element with a specific key.
      myCol.Remove("red")
      Console.WriteLine("After removing the element with the key ""red"" (Count = {0}):", myCol.Count)
      PrintKeysAndValues(myCol)

   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
'After removing the element at index 1 (Count = 2):
'[0] : red, apple
'[1] : green, pear
'After removing the element with the key "red" (Count = 1):
'[0] : green, 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 );
      }
   }

   // 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 );
      }
   }

   // 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 );
   }

}

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 );

      // Removes an element at a specific index.
      myCol.Remove( 1 );
      Console.WriteLine( "After removing the element at index 1 (Count = {0}):", myCol.Count );
      PrintKeysAndValues( myCol );

      // Removes an element with a specific key.
      myCol.Remove( "red" );
      Console.WriteLine( "After removing the element with the key \"red\" (Count = {0}):", myCol.Count );
      PrintKeysAndValues( myCol );

   }

   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
After removing the element at index 1 (Count = 2):
[0] : red, apple
[1] : green, pear
After removing the element with the key "red" (Count = 1):
[0] : green, pear

*/

[C++] 
#using <mscorlib.dll>
#using <system.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;

public __gc class MyCollection : public NameObjectCollectionBase 
{

private:
   DictionaryEntry _de;

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

   // Adds elements from an IDictionary* into the new collection.
   MyCollection(IDictionary* d) 
   {
      IEnumerator* myEnum = d->GetEnumerator();
      while (myEnum->MoveNext()) 
      {
         DictionaryEntry* de = __try_cast<DictionaryEntry*>(myEnum->Current);
         this->BaseAdd(__try_cast<String*>(de->Key), de->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);
   }
};

void PrintKeysAndValues(MyCollection* myCol)
{
   for (int i = 0; i < myCol->Count; i++)
   {
      Console::WriteLine(S"[{0}] : {1}, {2}", __box(i), myCol->Item[i].Key, myCol->Item[i].Value);
   }
};

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

   // Removes an element at a specific index.
   myCol->Remove(1);
   Console::WriteLine(S"After removing the element at index 1 (Count = {0}):", __box(myCol->Count));
   PrintKeysAndValues(myCol);

   // Removes an element with a specific key.
   myCol->Remove(S"red");
   Console::WriteLine(S"After removing the element with the key \"red\" (Count = {0}):", __box(myCol->Count));
      PrintKeysAndValues(myCol);
}

/*
This code produces the following output.

Initial state of the collection (Count = 3):
[0] : red, apple
[1] : yellow, banana
[2] : green, pear
After removing the element at index 1 (Count = 2):
[0] : red, apple
[1] : green, pear
After removing the element with the key "red" (Count = 1):
[0] : green, pear

*/

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework

See Also

NameObjectCollectionBase Class | NameObjectCollectionBase Members | System.Collections.Specialized Namespace | Performing Culture-Insensitive String Operations

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