ArrayList.Reverse Method (Int32, Int32)
.NET Framework (current version)
Reverses the order of the elements in the specified range.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- index
-
Type:
System.Int32
The zero-based starting index of the range to reverse.
- count
-
Type:
System.Int32
The number of elements in the range to reverse.
| Exception | Condition |
|---|---|
| ArgumentOutOfRangeException | index is less than zero. -or- count is less than zero. |
| ArgumentException | index and count do not denote a valid range of elements in the ArrayList. |
| NotSupportedException | The ArrayList is read-only. |
This method uses Array.Reverse to reverse the order of the elements, such that the element at ArrayList [i], where i is any index within the range, moves to ArrayList [j], where j equals index + index + count - i - 1.
This method is an O(n) operation, where n is count.
The following code example shows how to reverse the sort order of the values in a range of elements 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) ' Reverses the sort order of the values of the ArrayList. myAL.Reverse(1, 3) ' Displays the values of the ArrayList. Console.WriteLine("After reversing:") 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 reversing: ' The ' FOX ' BROWN ' QUICK ' jumps ' over ' the ' lazy ' dog
Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
Available since 10
.NET Framework
Available since 1.1
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