Visual Basic.net ArrayList 用法

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ArrayList代表一个动态的，此类实现大小可动态调整的对象数组，提供了一般的集合功能，适合于大多数用户应用。

ArrayList有三个构造器:

1．ArrayList()

　　直接实例化，后调用方法添加或者删除列表条目

Dim pan1 as New ArrayList()pan1.add(“number1”)dim arr1 as New Collectionarr1.add(“number2”)arr1.add(“ss3”)pan1.addrange(arr1)

2．ArrayList(int32)

给 ArrayList的构造器传递一个整数，以设定ArrayList的初始容量。

Dim pan1 as ArrayList(5) ‘设定ArrayList初始容量Dim cc as Collectioncc.add(string1)cc.add(string2)pan1.addrange(cc)pan1.capacity=8    ‘将arraylist容量重新设定为8MsgBox(pan1.capacity)‘TrimToSize()方法将arraylist容量压缩成实际的元素数量‘pan1.capacity 与pan1.trimtosize()及pan1.count等价pan1.trimtosize()

3.ArrayList(ICollection)

ArrayList的构造器可以接受一个集合

Dim cc As New Collectioncc.add("string1")cc.Add("string2")Dim pan1 As New ArrayList(cc)

实例:

Imports SystemImports System.CollectionsImports Microsoft.VisualBasicPublic Class SamplesArrayList        Public Shared Sub Main()        ' Creates and initializes a new ArrayList.        Dim myAL As New ArrayList()        myAL.Add("Hello")        myAL.Add("World")        myAL.Add("!")        ' Displays the properties and values of the ArrayList.        Console.WriteLine("myAL")        Console.WriteLine("    Count:    {0}", myAL.Count)        Console.WriteLine("    Capacity: {0}", myAL.Capacity)        Console.Write("    Values:")        PrintValues(myAL)    End Sub    Public Shared Sub PrintValues(myList As IEnumerable)        Dim obj As [Object]        For Each obj In  myList            Console.Write("   {0}", obj)        Next obj        Console.WriteLine()    End Sub 'PrintValuesEnd Class

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