List(T) Constructor (Int32)
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List(T) Constructor (Int32)

Initializes a new instance of the List(T) class that is empty and has the specified initial capacity.

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

new : 
        capacity:int -> List


Type: System.Int32
The number of elements that the new list can initially store.


capacity is less than 0.

The capacity of a List(T) is the number of elements that the List(T) can hold. As elements are added to a List(T), the capacity is automatically increased as required by reallocating the internal array.

If the size of the collection can be estimated, specifying the initial capacity eliminates the need to perform a number of resizing operations while adding elements to the List(T).

The capacity can be decreased by calling the TrimExcess method or by setting the Capacity property explicitly. Decreasing the capacity reallocates memory and copies all the elements in the List(T).

This constructor is an O(n) operation, where n is capacity.

The following code example demonstrates the List(T)(Int32) constructor. A List(T) of strings with a capacity of 4 is created, because the ultimate size of the list is known to be exactly 4. The list is populated with four strings, and a read-only copy is created by using the AsReadOnly method.

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

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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