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VB.NET Reverse String

This VB.NET example program reverses the characters in Strings. It uses Array.Reverse.
Reverse String. A String contains individual characters. The order of these characters can be reversed. In VB.NET we reverse a string using the ToCharArray function. We use next the Array.Reverse subroutine the String constructor.
Example. Here we define a function Reverse that accepts on String argument and returns a String. Then we store the value returned by ToCharArray in a local variable. Next pass that variable to the Array.Reverse subroutine.Array

Info: Reverse internally rearranges the characters in the array to be in the opposite order.

Finally: You must invoke the String constructor. This converts the reversed character array back into a string.

VB.NET program that reverses strings Module Module1 Sub Main() ' Test. Console.WriteLine(Reverse("perls")) Console.WriteLine(Reverse("sam")) Console.WriteLine(Reverse(Reverse("perls"))) End Sub ''' <summary> ''' Reverse input string. ''' </summary> Function Reverse(ByVal value As String) As String ' Convert to char array. Dim arr() As Char = value.ToCharArray() ' Use Array.Reverse function. Array.Reverse(arr) ' Construct new string. Return New String(arr) End Function End Module Output slrep mas perls
Interviews. Readers have commented that in interview questions, the classic question of writing a method to reverse a string often have some constraints. For example, you might be required not to call methods such as Array.Reverse.

However: Even with these constraints, you would likely need to use the String constructor or possibly ToCharArray.

ToCharArray
Summary. It has little practical application in real applications. But learning to reverse a string in the VB.NET language is both informative and elucidating. Strings in VB.NET cannot be manipulated directly. They are immutable.

Instead: You must convert them to character arrays with the ToCharArray function.

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