Reverse

[tk.unlimited]

Hey ALL!!

Im having troubles with Reversing text from a text box. e.g If the sentence is Hello there then ereht olleH is displayed.. To use the LEN function and accessing a single character with sSentence.chars(icounter) <--- From For LOOP

Tk Unlimited!!

 

[kulrom]

First off vb.net is exposing .Lenght method as vb6 Len command equivalent (so, you shouldn't use a Len function if further ... )

Second off, you haven't explained ver well what is the problem there ... so try to explain the problem you have and i'll try to resolve ... Cheers

 

[kulrom]

Btw, if you wish to flip around the front and back end of a string, then the StrReverse(string) is for you.

next code is reversing the string:

Dim strRev AsString = StrReverse("Hello there")
 
MessageBox.Show(strRev)

or Simply

MessageBox.Show(StrReverse("Hello there"))

Cheers

 

[Paszt]

strange, StrReverse is a member of the same class as the Len function (Microsoft.VisualBasic.Strings) .

If you wish not to use the Microsoft.VisualBasic namespace (which is up to debate), here's a simple recursive function:

Function ReverseString(ByVal str As String) As String
    If str.Length = 1 Then
        Return str
    Else
        Return ReverseString(str.Substring(1)) + str.Substring(0, 1)
    End If
End Function

 

[kulrom]

Good note Paszt ... sharp eye thanks for the point
btw, your function looks fine to me (namely, i'm using something very similar for the purpose and you were right about VisualBasic namespace, we should tend to avoid it whenever we are in possibility to do the same)

Cheers

 

[jmcilhinney]

I'm in favour of using System-based alternatives to VB.NET Runtime functions if they exist. Given that there is no direct alternative to StrReverse I would recommend using it in this case. If you do want to avoid Runtime functions, here's a non-recursive alternative that avoids excessive string manipulation:

	Public Function StrReverse(ByVal str As String) As String
		Dim chars As Char() = str.ToCharArray()

		Array.Reverse(chars)
		Return New String(chars)
	End Function