List<T>.InsertRange Method

Inserts the elements of a collection into the List<T> at the specified index.

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

public void InsertRange(
	int index,
	IEnumerable<T> collection
)

Parameters

index
Type: System.Int32

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

collection
Type: System.Collections.Generic.IEnumerable<T>

The collection whose elements should be inserted into the List<T>. The collection itself cannot be null, but it can contain elements that are null, if type T is a reference type.

ExceptionCondition
ArgumentNullException

collection is null.

ArgumentOutOfRangeException

index is less than 0.

-or-

index is greater than Count.

List<T> accepts null 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<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<T>.

The order of the elements in the collection is preserved in the List<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 code example demonstrates InsertRange method and various other methods of the List<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.

using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        string[] input = { "Brachiosaurus", 
                           "Amargasaurus", 
                           "Mamenchisaurus" };

        List<string> dinosaurs = new List<string>(input);

        Console.WriteLine("\nCapacity: {0}", dinosaurs.Capacity);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nAddRange(dinosaurs)");
        dinosaurs.AddRange(dinosaurs);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nRemoveRange(2, 2)");
        dinosaurs.RemoveRange(2, 2);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        input = new string[] { "Tyrannosaurus", 
                               "Deinonychus", 
                               "Velociraptor"};

        Console.WriteLine("\nInsertRange(3, input)");
        dinosaurs.InsertRange(3, input);

        Console.WriteLine();
        foreach( string dinosaur in dinosaurs )
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\noutput = dinosaurs.GetRange(2, 3).ToArray()");
        string[] output = dinosaurs.GetRange(2, 3).ToArray();

        Console.WriteLine();
        foreach( string dinosaur in output )
        {
            Console.WriteLine(dinosaur);
        }
    }
}

/* 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
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