List<T>.AddRange Method
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Adds the elements of the specified collection to the end of the List<T>.
Namespace: System.Collections.Generic
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Sub AddRange ( _
collection As IEnumerable(Of T) _
)
public void AddRange(
IEnumerable<T> collection
)
Parameters
- collection
Type: System.Collections.Generic.IEnumerable<T>
The collection whose elements should be added to the end of the List<T>. The collection itself cannot be nulla null reference (Nothing in Visual Basic), but it can contain elements that are nulla null reference (Nothing in Visual Basic), if type T is a reference type.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentNullException | collection is nulla null reference (Nothing in Visual Basic). |
Remarks
The order of the elements in the collection is preserved in the List<T>.
If the new Count (the current Count plus the size of the collection) will be greater than Capacity, the capacity of the List<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 the List<T> can accommodate the new elements without increasing the Capacity, this method is an O(n) operation, where n is the number of elements to be added. If the capacity needs to be increased to accommodate the new elements, this method becomes an O(n + m) operation, where n is the number of elements to be added and m is Count.
Examples
The following code example demonstrates the AddRange method and various other methods of the List<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 AddRange method is called, with the list as its argument. The result is that the current elements of the list are added to the end of the list, duplicating all the elements.
Imports System.Collections.Generic
Public Class Example
Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
Dim input() As String = {"Brachiosaurus", _
"Amargasaurus", _
"Mamenchisaurus"}
Dim dinosaurs As New List(Of String)(input)
outputBlock.Text += String.Format(vbLf & "Capacity: {0}", dinosaurs.Capacity) & vbCrLf
outputBlock.Text &= vbCrLf
For Each dinosaur As String In dinosaurs
outputBlock.Text &= dinosaur & vbCrLf
Next
outputBlock.Text &= vbLf & "AddRange(dinosaurs)" & vbCrLf
dinosaurs.AddRange(dinosaurs)
outputBlock.Text &= vbCrLf
For Each dinosaur As String In dinosaurs
outputBlock.Text &= dinosaur & vbCrLf
Next
outputBlock.Text += String.Format(vbLf & "RemoveRange(2, 2)") & vbCrLf
dinosaurs.RemoveRange(2, 2)
outputBlock.Text &= vbCrLf
For Each dinosaur As String In dinosaurs
outputBlock.Text &= dinosaur & vbCrLf
Next
input = New String() {"Tyrannosaurus", _
"Deinonychus", _
"Velociraptor"}
outputBlock.Text += String.Format(vbLf & "InsertRange(3, input)") & vbCrLf
dinosaurs.InsertRange(3, input)
outputBlock.Text &= vbCrLf
For Each dinosaur As String In dinosaurs
outputBlock.Text &= dinosaur & vbCrLf
Next
outputBlock.Text += String.Format(vbLf & "output = dinosaurs.GetRange(2, 3).ToArray") & vbCrLf
Dim output() As String = dinosaurs.GetRange(2, 3).ToArray()
outputBlock.Text &= vbCrLf
For Each dinosaur As String In output
outputBlock.Text &= dinosaur & vbCrLf
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
using System;
using System.Collections.Generic;
public class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
string[] input = { "Brachiosaurus",
"Amargasaurus",
"Mamenchisaurus" };
List<string> dinosaurs = new List<string>(input);
outputBlock.Text += String.Format("\nCapacity: {0}", dinosaurs.Capacity) + "\n";
outputBlock.Text += "\n";
foreach (string dinosaur in dinosaurs)
{
outputBlock.Text += dinosaur + "\n";
}
outputBlock.Text += "\nAddRange(dinosaurs)" + "\n";
dinosaurs.AddRange(dinosaurs);
outputBlock.Text += "\n";
foreach (string dinosaur in dinosaurs)
{
outputBlock.Text += dinosaur + "\n";
}
outputBlock.Text += String.Format("\nRemoveRange(2, 2)") + "\n";
dinosaurs.RemoveRange(2, 2);
outputBlock.Text += "\n";
foreach (string dinosaur in dinosaurs)
{
outputBlock.Text += dinosaur + "\n";
}
input = new string[] { "Tyrannosaurus",
"Deinonychus",
"Velociraptor"};
outputBlock.Text += String.Format("\nInsertRange(3, input)") + "\n";
dinosaurs.InsertRange(3, input);
outputBlock.Text += "\n";
foreach (string dinosaur in dinosaurs)
{
outputBlock.Text += dinosaur + "\n";
}
outputBlock.Text += String.Format("\noutput = dinosaurs.GetRange(2, 3).ToArray()") + "\n";
string[] output = dinosaurs.GetRange(2, 3).ToArray();
outputBlock.Text += "\n";
foreach (string dinosaur in output)
{
outputBlock.Text += dinosaur + "\n";
}
}
}
/* 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
*/
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
XNA Framework
Supported in: Xbox 360, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.