ArrayList.Add(Object) メソッド

public:
 virtual int Add(System::Object ^ value);

public virtual int Add (object value);

public virtual int Add (object? value);

abstract member Add : obj -> int
override this.Add : obj -> int

Public Overridable Function Add (value As Object) As Integer

パラメーター

戻り値

Int32

value が追加された位置の ArrayList インデックス。The ArrayList index at which the value has been added.

実装

例外

例

次のコード例は、に要素を追加する方法を示して ArrayList います。The following code example shows how to add elements to the ArrayList.

using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList, char mySeparator );
int main()
{
   
   // Creates and initializes a new ArrayList.
   ArrayList^ myAL = gcnew ArrayList;
   myAL->Add( "The" );
   myAL->Add( "quick" );
   myAL->Add( "brown" );
   myAL->Add( "fox" );
   
   // Creates and initializes a new Queue.
   Queue^ myQueue = gcnew Queue;
   myQueue->Enqueue( "jumps" );
   myQueue->Enqueue( "over" );
   myQueue->Enqueue( "the" );
   myQueue->Enqueue( "lazy" );
   myQueue->Enqueue( "dog" );
   
   // Displays the ArrayList and the Queue.
   Console::WriteLine( "The ArrayList initially contains the following:" );
   PrintValues( myAL, '\t' );
   Console::WriteLine( "The Queue initially contains the following:" );
   PrintValues( myQueue, '\t' );
   
   // Copies the Queue elements to the end of the ArrayList.
   myAL->AddRange( myQueue );
   
   // Displays the ArrayList.
   Console::WriteLine( "The ArrayList now contains the following:" );
   PrintValues( myAL, '\t' );
}

void PrintValues( IEnumerable^ myList, char mySeparator )
{
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ obj = safe_cast<Object^>(myEnum->Current);
      Console::Write( "{0}{1}", mySeparator, obj );
   }

   Console::WriteLine();
}

/* 
This code produces the following output.

The ArrayList initially contains the following:
    The    quick    brown    fox
The Queue initially contains the following:
    jumps    over    the    lazy    dog
The ArrayList now contains the following:
    The    quick    brown    fox    jumps    over    the    lazy    dog
*/

using System;
using System.Collections;
public class SamplesArrayList  {

   public static void Main()  {

      // Creates and initializes a new ArrayList.
      ArrayList myAL = new ArrayList();
      myAL.Add( "The" );
      myAL.Add( "quick" );
      myAL.Add( "brown" );
      myAL.Add( "fox" );

      // Creates and initializes a new Queue.
      Queue myQueue = new Queue();
      myQueue.Enqueue( "jumps" );
      myQueue.Enqueue( "over" );
      myQueue.Enqueue( "the" );
      myQueue.Enqueue( "lazy" );
      myQueue.Enqueue( "dog" );

      // Displays the ArrayList and the Queue.
      Console.WriteLine( "The ArrayList initially contains the following:" );
      PrintValues( myAL, '\t' );
      Console.WriteLine( "The Queue initially contains the following:" );
      PrintValues( myQueue, '\t' );

      // Copies the Queue elements to the end of the ArrayList.
      myAL.AddRange( myQueue );

      // Displays the ArrayList.
      Console.WriteLine( "The ArrayList now contains the following:" );
      PrintValues( myAL, '\t' );
   }

   public static void PrintValues( IEnumerable myList, char mySeparator )  {
      foreach ( Object obj in myList )
         Console.Write( "{0}{1}", mySeparator, obj );
      Console.WriteLine();
   }
}


/*
This code produces the following output.

The ArrayList initially contains the following:
    The    quick    brown    fox
The Queue initially contains the following:
    jumps    over    the    lazy    dog
The ArrayList now contains the following:
    The    quick    brown    fox    jumps    over    the    lazy    dog
*/

Imports System.Collections

Public Class SamplesArrayList    
    
    Public Shared Sub Main()
        
        ' Creates and initializes a new ArrayList.
        Dim myAL As New ArrayList()
        myAL.Add("The")
        myAL.Add("quick")
        myAL.Add("brown")
        myAL.Add("fox")
        
        ' Creates and initializes a new Queue.
        Dim myQueue As New Queue()
        myQueue.Enqueue("jumps")
        myQueue.Enqueue("over")
        myQueue.Enqueue("the")
        myQueue.Enqueue("lazy")
        myQueue.Enqueue("dog")
        
        ' Displays the ArrayList and the Queue.
        Console.WriteLine("The ArrayList initially contains the following:")
        PrintValues(myAL, ControlChars.Tab)
        Console.WriteLine("The Queue initially contains the following:")
        PrintValues(myQueue, ControlChars.Tab)
        
        ' Copies the Queue elements to the end of the ArrayList.
        myAL.AddRange(myQueue)
        
        ' Displays the ArrayList.
        Console.WriteLine("The ArrayList now contains the following:")
        PrintValues(myAL, ControlChars.Tab)
    End Sub

    Public Shared Sub PrintValues(myList As IEnumerable, mySeparator As Char)
        Dim obj As [Object]
        For Each obj In  myList
          Console.Write( "{0}{1}", mySeparator, obj )
        Next obj
        Console.WriteLine()
    End Sub

End Class


' This code produces the following output.
' 
' The ArrayList initially contains the following:
'     The    quick    brown    fox
' The Queue initially contains the following:
'     jumps    over    the    lazy    dog
' The ArrayList now contains the following:
'     The    quick    brown    fox    jumps    over    the    lazy    dog 

注釈

ArrayListnullは、有効な値としてを受け入れ、重複する要素を許可します。ArrayList accepts null as a valid value and allows duplicate elements.

が Count 既にに等しい場合は Capacity 、の容量が増加し、内部配列が自動的に再割り当てされ ArrayList ます。新しい要素が追加される前に、既存の要素が新しい配列にコピーされます。If Count already equals Capacity, the capacity of the ArrayList is increased by automatically reallocating the internal array, and the existing elements are copied to the new array before the new element is added.

Countがより小さい場合 Capacity 、このメソッドは O(1) 操作です。If Count is less than Capacity, this method is an O(1) operation. 新しい要素を格納するために容量を増やす必要がある場合、このメソッド O(n) は操作になります。ここで、 n は Count です。If the capacity needs to be increased to accommodate the new element, this method becomes an O(n) operation, where n is Count.

適用対象

こちらもご覧ください

• AddRange(ICollection)
• Insert(Int32, Object)
• Remove(Object)
• Count