List.List(Generic IEnumerable) Constructor
Assembly: mscorlib (in mscorlib.dll)
The capacity of a List is the number of elements that the List can hold. As elements are added to a List, 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.
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.
The elements are copied onto the List in the same order they are read by the enumerator of the collection.
This constructor is an O(n) operation, where n is the number of elements in collection.
The following code example demonstrates the List constructor and various methods of the List 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 Capacity property is then displayed, to show that the initial capacity is exactly what is required to hold the input elements.
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 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.