List(Of T) Constructor (IEnumerable(Of T))

Initializes a new instance of the List(Of T) class that contains elements copied from the specified collection and has sufficient capacity to accommodate the number of elements copied.

Namespace:  System.Collections.Generic
Assembly:  mscorlib (in mscorlib.dll)

'Declaration
Public Sub New ( _
	collection As IEnumerable(Of T) _
)
'Usage
Dim collection As IEnumerable(Of T)

Dim instance As New List(collection)

Parameters

collection
Type: System.Collections.Generic.IEnumerable(Of T)

The collection whose elements are copied to the new list.

ExceptionCondition
ArgumentNullException

collection is Nothing.

The elements are copied onto the List(Of T) in the same order they are read by the enumerator of the collection.

This constructor is an O(n) operation, where n is the number of elements in collection.

The following code example demonstrates the List(Of T) constructor and various methods of the List(Of T) class that act on ranges. An array of strings is created and passed to the constructor, populating the list with the elements of the array. The Capacity property is then displayed, to show that the initial capacity is exactly what is required to hold the input elements.

Imports System
Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main()

        Dim input() As String = { "Brachiosaurus", _
                                  "Amargasaurus", _
                                  "Mamenchisaurus" }

        Dim dinosaurs As New List(Of String)(input)

        Console.WriteLine(vbLf & "Capacity: {0}", dinosaurs.Capacity)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "AddRange(dinosaurs)")
        dinosaurs.AddRange(dinosaurs)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "RemoveRange(2, 2)")
        dinosaurs.RemoveRange(2, 2)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        input = New String() { "Tyrannosaurus", _
                               "Deinonychus", _
                               "Velociraptor" }

        Console.WriteLine(vbLf & "InsertRange(3, input)")
        dinosaurs.InsertRange(3, input)

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "output = dinosaurs.GetRange(2, 3).ToArray")
        Dim output() As String = dinosaurs.GetRange(2, 3).ToArray()

        Console.WriteLine()
        For Each dinosaur As String In output
            Console.WriteLine(dinosaur)
        Next 

    End Sub 
End Class 

' This code example produces the following output: 

'Capacity: 3 

'Brachiosaurus 
'Amargasaurus 
'Mamenchisaurus 

'AddRange(dinosaurs) 

'Brachiosaurus 
'Amargasaurus 
'Mamenchisaurus 
'Brachiosaurus 
'Amargasaurus 
'Mamenchisaurus 

'RemoveRange(2, 2) 

'Brachiosaurus 
'Amargasaurus 
'Amargasaurus 
'Mamenchisaurus 

'InsertRange(3, input) 

'Brachiosaurus 
'Amargasaurus 
'Amargasaurus 
'Tyrannosaurus 
'Deinonychus 
'Velociraptor 
'Mamenchisaurus 

'output = dinosaurs.GetRange(2, 3).ToArray 

'Amargasaurus 
'Tyrannosaurus 
'Deinonychus

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

.NET Compact Framework

Supported in: 3.5, 2.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback

Community Additions

ADD
Show:
© 2014 Microsoft