如何在C#中创建ArrayList（用法示例） _C#特性

ArrayList()构造函数用于初始化ArrayList类的新实例, 该实例将为空并具有默认的初始容量。数组列表表示可以单独索引的对象的有序集合。它基本上是数组的替代方法。它还允许动态分配内存, 添加, 搜索和排序列表中的项目。
【如何在C#中创建ArrayList（用法示例）】语法如下：

public ArrayList ();

重要事项：

ArrayList可以容纳的元素数称为容量ArrayList。如果将元素添加到ArrayList中, 则将通过重新分配内部数组来自动增加容量。
如果可以估计集合的大小, 则指定初始容量将消除在将元素添加到ArrayList时执行大量调整大小操作的需求。
此构造函数是O(1)操作。

示例1：

//C# Program to illustrate how //to create a ArrayList using System; using System.Collections; class Geeks {//Main Method public static void Main(String[] args) {//arrlist is the ArrayList object //ArrayList() is the constructor //used to initializes a new //instance of the ArrayList class ArrayList arrlist = new ArrayList(); //Count property is used to get the //number of elements in ArrayList //It will give 0 as no elements //are present currently Console.WriteLine(arrlist.Count); } }

输出如下：

0

示例2：

//C# Program to illustrate how //to create a ArrayList using System; using System.Collections; class Geeks {//Main Method public static void Main(String[] args) {//arrlist is the ArrayList object //ArrayList() is the constructor //used to initializes a new //instance of the ArrayList class ArrayList arrlist = new ArrayList(); Console.Write( "Before Add Method: " ); //Count property is used to get the //number of elements in ArrayList //It will give 0 as no elements //are present currently Console.WriteLine(arrlist.Count); //Adding the elements //to the ArrayList arrlist.Add( "This" ); arrlist.Add( "is" ); arrlist.Add( "C#" ); arrlist.Add( "ArrayList" ); Console.Write( "After Add Method: " ); //Count property is used to get the //number of elements in arrlist Console.WriteLine(arrlist.Count); } }

输出如下：