List(Of T).InsertRange Method

Inserts the elements of a collection into the List(Of T) at the specified index.

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

'Declaration
Public Sub InsertRange ( _
	index As Integer, _
	collection As IEnumerable(Of T) _
)

Parameters

index
Type: System.Int32

The zero-based index at which the new elements should be inserted.

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

The collection whose elements should be inserted into the List(Of T). The collection itself cannot be Nothing, but it can contain elements that are Nothing, if type T is a reference type.

ExceptionCondition
ArgumentNullException

collection is Nothing.

ArgumentOutOfRangeException

index is less than 0.

-or-

index is greater than Count.

List(Of T) accepts Nothing as a valid value for reference types and allows duplicate elements.

If the new Count (the current Count plus the size of the collection) will be greater than Capacity, the capacity of the List(Of T) is increased by automatically reallocating the internal array to accommodate the new elements, and the existing elements are copied to the new array before the new elements are added.

If index is equal to Count, the elements are added to the end of List(Of T).

The order of the elements in the collection is preserved in the List(Of T).

This method is an O(n + m) operation, where n is the number of elements to be added and m is Count.

The following example demonstrates InsertRange method and various other methods of the List(Of T) class that act on ranges. After the list has been created and populated with the names of several peaceful plant-eating dinosaurs, the InsertRange method is used to insert an array of three ferocious meat-eating dinosaurs into the list, beginning at index location 3.

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

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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