Array.Reverse Method (Array, Int32, Int32)
Reverses the sequence of the elements in a range of elements in the one-dimensional Array.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- array
-
Type:
System.Array
The one-dimensional Array to reverse.
- index
-
Type:
System.Int32
The starting index of the section to reverse.
- length
-
Type:
System.Int32
The number of elements in the section to reverse.
| Exception | Condition |
|---|---|
| ArgumentNullException | array is null. |
| RankException | array is multidimensional. |
| ArgumentOutOfRangeException | index is less than the lower bound of array. -or- length is less than zero. |
| ArgumentException | index and length do not specify a valid range in array. |
After a call to this method, the element at myArray[i], where i is any index in the array, moves to myArray[j], where j equals (myArray.Length + myArray.GetLowerBound(0)) - (i - myArray.GetLowerBound(0)) - 1.
TheReverse method can be used to reverse a jagged array.
This method is an O(n) operation, where n is length.
The following code example shows how to reverse the sort of the values in a range of elements in an Array.
Imports System Imports Microsoft.VisualBasic Public Class SamplesArray Public Shared Sub Main() ' Creates and initializes a new Array. Dim myArray As Array = Array.CreateInstance(GetType(String), 9) myArray.SetValue("The", 0) myArray.SetValue("QUICK", 1) myArray.SetValue("BROWN", 2) myArray.SetValue("FOX", 3) myArray.SetValue("jumps", 4) myArray.SetValue("over", 5) myArray.SetValue("the", 6) myArray.SetValue("lazy", 7) myArray.SetValue("dog", 8) ' Displays the values of the Array. Console.WriteLine("The Array initially contains the " _ + "following values:") PrintIndexAndValues(myArray) ' Reverses the sort of the values of the Array. Array.Reverse(myArray, 1, 3) ' Displays the values of the Array. Console.WriteLine("After reversing:") PrintIndexAndValues(myArray) End Sub Public Shared Sub PrintIndexAndValues(myArray As Array) Dim i As Integer For i = myArray.GetLowerBound(0) To myArray.GetUpperBound(0) Console.WriteLine(ControlChars.Tab + "[{0}]:" + ControlChars.Tab _ + "{1}", i, myArray.GetValue(i)) Next i End Sub End Class ' This code produces the following output. ' ' The Array initially contains the following values: ' [0]: The ' [1]: QUICK ' [2]: BROWN ' [3]: FOX ' [4]: jumps ' [5]: over ' [6]: the ' [7]: lazy ' [8]: dog ' After reversing: ' [0]: The ' [1]: FOX ' [2]: BROWN ' [3]: QUICK ' [4]: jumps ' [5]: over ' [6]: the ' [7]: lazy ' [8]: dog
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1