List<'T> Constructor (Int32)

 
System_CAPS_noteNote

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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

Parameters

capacity
Type: System.Int32

The number of elements that the new list can initially store.

Exception Condition
ArgumentOutOfRangeException

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 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.

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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