ArrayList.Sort Method ()

 

Sorts the elements in the entire ArrayList.

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

Public Overridable Sub Sort

Exception Condition
NotSupportedException

The ArrayList is read-only.

This method uses Array.Sort, which uses the QuickSort algorithm. The QuickSort algorithm is a comparison sort (also called an unstable sort), which means that a "less than or equal to" comparison operation determines which of two elements should occur first in the final sorted list. However, if two elements are equal, their original order might not be preserved. In contrast, a stable sort preserves the order of elements that are equal. To perform a stable sort, you must implement a custom IComparer interface to use with the other overloads of this method.

On average, this method is an O(n log n) operation, where n is Count; in the worst case it is an O(n^2) operation.

The following code example shows how to sort the values in an ArrayList.

Imports System
Imports System.Collections

Public Class SamplesArrayList

    Public Shared Sub Main()

        ' Creates and initializes a new ArrayList.
        Dim myAL As New ArrayList()
        myAL.Add("The")
        myAL.Add("quick")
        myAL.Add("brown")
        myAL.Add("fox")
        myAL.Add("jumps")
        myAL.Add("over")
        myAL.Add("the")
        myAL.Add("lazy")
        myAL.Add("dog")

        ' Displays the values of the ArrayList.
        Console.WriteLine("The ArrayList initially contains the following values:")
        PrintValues(myAL)

        ' Sorts the values of the ArrayList.
        myAL.Sort()

        ' Displays the values of the ArrayList.
        Console.WriteLine("After sorting:")
        PrintValues(myAL)

    End Sub 'Main

    Public Shared Sub PrintValues(myList As IEnumerable)
        Dim obj As [Object]
        For Each obj In  myList
            Console.WriteLine("   {0}", obj)
        Next obj
        Console.WriteLine()
    End Sub 'PrintValues

End Class 'SamplesArrayList 


' This code produces the following output.
'
' The ArrayList initially contains the following values:
'    The
'    quick
'    brown
'    fox
'    jumps
'    over
'    the
'    lazy
'    dog
'
' After sorting:
'    brown
'    dog
'    fox
'    jumps
'    lazy
'    over
'    quick
'    the
'    The

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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