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List(T).AddRange Method

Adds the elements of the specified collection to the end of the List(T).

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

member AddRange : 
        collection:IEnumerable<'T> -> unit


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 a null reference (Nothing in Visual Basic), but it can contain elements that are a null reference (Nothing in Visual Basic), if type T is a reference type.


collection is a null reference (Nothing in Visual Basic).

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.

The following 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.

No code example is currently available or this language may not be supported.

.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

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
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