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ArrayList.ToArray Method

Definition

Copies the elements of the ArrayList to a new array.

Overloads

ToArray()

Copies the elements of the ArrayList to a new Object array.

ToArray(Type)

Copies the elements of the ArrayList to a new array of the specified element type.

ToArray()

Source:
ArrayList.cs
Source:
ArrayList.cs
Source:
ArrayList.cs

Copies the elements of the ArrayList to a new Object array.

public:
 virtual cli::array <System::Object ^> ^ ToArray();
public virtual object[] ToArray ();
public virtual object?[] ToArray ();
abstract member ToArray : unit -> obj[]
override this.ToArray : unit -> obj[]
Public Overridable Function ToArray () As Object()

Returns

Object[]

An Object array containing copies of the elements of the ArrayList.

Remarks

The elements are copied using Array.Copy, which is an O(n) operation, where n is Count.

Applies to

ToArray(Type)

Source:
ArrayList.cs
Source:
ArrayList.cs
Source:
ArrayList.cs

Copies the elements of the ArrayList to a new array of the specified element type.

public:
 virtual Array ^ ToArray(Type ^ type);
public virtual Array ToArray (Type type);
abstract member ToArray : Type -> Array
override this.ToArray : Type -> Array
Public Overridable Function ToArray (type As Type) As Array

Parameters

type
Type

The element Type of the destination array to create and copy elements to.

Returns

An array of the specified element type containing copies of the elements of the ArrayList.

Exceptions

type is null.

The type of the source ArrayList cannot be cast automatically to the specified type.

Examples

The following copy example shows how to copy the elements of an ArrayList to a string array.

using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( ArrayList^ myList );
void PrintIndexAndValues( array<String^>^myArr );
int main()
{
   // Creates and initializes a new ArrayList.
   ArrayList^ myAL = gcnew ArrayList;
   myAL->Add( "The" );
   myAL->Add( "quick" );
   myAL->Add( "brown" );
   myAL->Add( "fox" );
   myAL->Add( "jumps" );
   myAL->Add( "over" );
   myAL->Add( "the" );
   myAL->Add( "lazy" );
   myAL->Add( "dog" );

   // Displays the values of the ArrayList.
   Console::WriteLine( "The ArrayList contains the following values:" );
   PrintIndexAndValues( myAL );

   // Copies the elements of the ArrayList to a string array.
   array<String^>^myArr = reinterpret_cast<array<String^>^>(myAL->ToArray( String::typeid ));

   // Displays the contents of the string array.
   Console::WriteLine( "The string array contains the following values:" );
   PrintIndexAndValues( myArr );
}

void PrintIndexAndValues( ArrayList^ myList )
{
   int i = 0;
   IEnumerator^ myEnum = myList->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Object^ o = safe_cast<Object^>(myEnum->Current);
      Console::WriteLine( "\t[{0}]:\t{1}", i++, o );
   }

   Console::WriteLine();
}

void PrintIndexAndValues( array<String^>^myArr )
{
   for ( int i = 0; i < myArr->Length; i++ )
      Console::WriteLine( "\t[{0}]:\t{1}", i, myArr[ i ] );
   Console::WriteLine();
}

/* 
This code produces the following output.

The ArrayList contains the following values:
        [0]:    The
        [1]:    quick
        [2]:    brown
        [3]:    fox
        [4]:    jumps
        [5]:    over
        [6]:    the
        [7]:    lazy
        [8]:    dog

The string array contains the following values:
        [0]:    The
        [1]:    quick
        [2]:    brown
        [3]:    fox
        [4]:    jumps
        [5]:    over
        [6]:    the
        [7]:    lazy
        [8]:    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" );
      myAL.Add( "jumps" );
      myAL.Add( "over" );
      myAL.Add( "the" );
      myAL.Add( "lazy" );
      myAL.Add( "dog" );

      // Displays the values of the ArrayList.
      Console.WriteLine( "The ArrayList contains the following values:" );
      PrintIndexAndValues( myAL );

      // Copies the elements of the ArrayList to a string array.
      String[] myArr = (String[]) myAL.ToArray( typeof( string ) );

      // Displays the contents of the string array.
      Console.WriteLine( "The string array contains the following values:" );
      PrintIndexAndValues( myArr );
   }

   public static void PrintIndexAndValues( ArrayList myList )  {
      int i = 0;
      foreach ( Object o in myList )
         Console.WriteLine( "\t[{0}]:\t{1}", i++, o );
      Console.WriteLine();
   }

   public static void PrintIndexAndValues( String[] myArr )  {
      for ( int i = 0; i < myArr.Length; i++ )
         Console.WriteLine( "\t[{0}]:\t{1}", i, myArr[i] );
      Console.WriteLine();
   }
}


/*
This code produces the following output.

The ArrayList contains the following values:
        [0]:    The
        [1]:    quick
        [2]:    brown
        [3]:    fox
        [4]:    jumps
        [5]:    over
        [6]:    the
        [7]:    lazy
        [8]:    dog

The string array contains the following values:
        [0]:    The
        [1]:    quick
        [2]:    brown
        [3]:    fox
        [4]:    jumps
        [5]:    over
        [6]:    the
        [7]:    lazy
        [8]:    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")
        myAL.Add("jumps")
        myAL.Add("over")
        myAL.Add("the")
        myAL.Add("lazy")
        myAL.Add("dog")

        ' Displays the values of the ArrayList.
        Console.WriteLine("The ArrayList contains the following values:")
        PrintIndexAndValues(myAL)

        ' Copies the elements of the ArrayList to a string array.
        Dim myArr As String() = CType(myAL.ToArray(GetType(String)), String())

        ' Displays the contents of the string array.
        Console.WriteLine("The string array contains the following values:")
        PrintIndexAndValues(myArr)

    End Sub

    Overloads Public Shared Sub PrintIndexAndValues(myList As ArrayList)
        Dim i As Integer = 0
        Dim o As [Object]
        For Each o In  myList
            Console.WriteLine("        [{0}]:    {1}", i, o)
            i = i + 1
        Next o
        Console.WriteLine()
    End Sub

    Overloads Public Shared Sub PrintIndexAndValues(myArr() As String)
        Dim i As Integer
        For i = 0 To myArr.Length - 1
            Console.WriteLine("        [{0}]:    {1}", i, myArr(i))
        Next i
        Console.WriteLine()
    End Sub

End Class


'This code produces the following output.
'
'The ArrayList contains the following values:
'        [0]:    The
'        [1]:    quick
'        [2]:    brown
'        [3]:    fox
'        [4]:    jumps
'        [5]:    over
'        [6]:    the
'        [7]:    lazy
'        [8]:    dog
'
'The string array contains the following values:
'        [0]:    The
'        [1]:    quick
'        [2]:    brown
'        [3]:    fox
'        [4]:    jumps
'        [5]:    over
'        [6]:    the
'        [7]:    lazy
'        [8]:    dog

Remarks

All of the objects in the ArrayList object will be cast to the Type specified in the type parameter.

The elements are copied using Array.Copy, which is an O(n) operation, where n is Count.

See also

Applies to