Reverse a string, word by word.

hi here is the complete code with screen shot.. u can easily understand it:

Imports System.IO
Imports System.Text


Public Class Form1
    Dim ofd As OpenFileDialog
    Dim strbldr As StringBuilder
    Dim arr() As String
    Dim i As Integer

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        'getting the file 
        ofd = New OpenFileDialog
        ofd.ShowDialog()
        Me.TextBox1.Text = ofd.FileName
       
    End Sub

    'Process
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        strbldr = New StringBuilder
        'storing the contents delemeted by space in arr array
        arr = strbldr.Append(File.ReadAllText(ofd.FileName).ToString()).ToString().Split(" ")

        ' reversing each word
        For i = 0 To arr.GetUpperBound(0)

            arr(i) = ReverseString(arr(i))
        Next

        strbldr = New StringBuilder

        'putting together all the reversed word
        For i = 0 To arr.GetUpperBound(0)
            strbldr.Append(arr(i))
            strbldr.Append(" ")
        Next

        ' writing to original file
        File.WriteAllText(ofd.FileName, strbldr.ToString())

    End Sub

    ' Reverse Function
    Public Function ReverseString(ByRef strToReverse As String) As String

        Dim result As String = ""

        For i As Integer = 0 To strToReverse.Length - 1

            result += strToReverse(strToReverse.Length - 1 - i)

        Next

        Return result

    End Function

End Class

i hope it helps

yeH syug!

woH nac I trevni ro( esrever, revetahw) a gnirts, tub gnisrever hcae drow?

ekiL:

sihT si a gnirts.
tuptuO:

This is a string.
dna ton:

string. a is This
oslA, woh nac I od ti ot a eritne elif?

sknahT ni ecnavda!

teL em wonk fi siht spleh.:D

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim myFile As String = "C:\test.txt" '// your File.
        If IO.File.Exists(myFile) Then '// Check if File.Exists.
            MsgBox(reverseFileContent(myFile)) '// Display Result.
            IO.File.WriteAllText(myFile, reverseFileContent(myFile)) '// Save Reversed File.
        Else : MsgBox("File Does Not Exist.")
        End If
    End Sub

    Function reverseFileContent(ByVal mySelectedFile As String) As String
        Dim arFileLines() As String = IO.File.ReadAllLines(mySelectedFile) '// Load each line as a String Array.
        Dim arWords() As String = Nothing '// used to Split. each line into Words.
        Dim sChar As String = Nothing '// used to get/set last char of word if not a Letter.
        Dim sTemp As String = Nothing '// used to save Reversed Lines.
        For iFileLineNumber As Integer = 0 To arFileLines.Length - 1 '// Loop thru all Lines.
            If arFileLines(iFileLineNumber).Contains(" "c) Then '// Check if Current Line Contains. a "space".
                arWords = arFileLines(iFileLineNumber).Split(" "c) '// Split. Line into Words by "space".
                For iWord As Integer = 0 To arWords.Length - 1  '// Loop thru all Words.
                    If Not arWords(iWord) = Nothing Then '// check if Word is not Nothing, since Words get Split. by " ".
                        If Char.IsLetter(CChar(arWords(iWord).Substring(arWords(iWord).Length - 1, 1))) Then '// check if Last Char is a Letter.
                            arWords(iWord) = StrReverse(arWords(iWord)) '// Reverse the Word.
                        Else '// if Last Char is NOT a Letter.
                            sChar = arWords(iWord).Substring(arWords(iWord).Length - 1, 1) '// get Last Char in Word.
                            '// Reverse Word without the Last Char, then add Last Char back to Word.
                            arWords(iWord) = StrReverse(arWords(iWord).Substring(0, arWords(iWord).Length - 1)) & sChar
                        End If
                        '// Add Reversed Words to String.
                        If Not iWord = arWords.Length - 1 Then : sTemp &= arWords(iWord) & " " '// if Not End of Line, add a "space".
                        Else : sTemp &= arWords(iWord) '// No "space".
                        End If
                    Else '// if Word is Nothing, since Words get Split. by " ", add the "space" back to keep File Format for Line Indenting.
                        sTemp &= " "
                    End If
                Next
            Else '// For Lines that DO NOT Contain Spaces, just a Single Word Line.
                If Not arFileLines(iFileLineNumber) = Nothing Then '// check if Word is not Nothing, since Words get Split. by " ".
                    If Char.IsLetter(CChar(arFileLines(iFileLineNumber).Substring(arFileLines(iFileLineNumber).Length - 1, 1))) Then '// check if Last Char is a Letter.
                        arFileLines(iFileLineNumber) = StrReverse(arFileLines(iFileLineNumber)) '// Reverse the Word.
                    Else '// if Last Char is NOT a Letter.
                        sChar = arFileLines(iFileLineNumber).Substring(arFileLines(iFileLineNumber).Length - 1, 1) '// get Last Char in Word.
                        '// Reverse Word without the Last Char, then add Last Char back to Word.
                        arFileLines(iFileLineNumber) = StrReverse(arFileLines(iFileLineNumber).Substring(0, arFileLines(iFileLineNumber).Length - 1)) & sChar
                    End If
                    sTemp &= arFileLines(iFileLineNumber)  '// Add Reversed Word to String.
                Else '// if Word is Nothing, since Words get Split. by " ", add the "space" back to keep File Format for Line Indenting.
                    sTemp &= " "
                End If
            End If
            If Not iFileLineNumber = arFileLines.Length - 1 Then sTemp &= vbNewLine '// Add Line Breaks if Not Last Line.
        Next
        Return sTemp '// Returns Reversed File Content.
    End Function
End Class

hi here is the complete code with screen shot.. u can easily understand it:

Imports System.IO
Imports System.Text


Public Class Form1
    Dim ofd As OpenFileDialog
    Dim strbldr As StringBuilder
    Dim arr() As String
    Dim i As Integer

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        'getting the file 
        ofd = New OpenFileDialog
        ofd.ShowDialog()
        Me.TextBox1.Text = ofd.FileName
       
    End Sub

    'Process
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        strbldr = New StringBuilder
        'storing the contents delemeted by space in arr array
        arr = strbldr.Append(File.ReadAllText(ofd.FileName).ToString()).ToString().Split(" ")

        ' reversing each word
        For i = 0 To arr.GetUpperBound(0)

            arr(i) = ReverseString(arr(i))
        Next

        strbldr = New StringBuilder

        'putting together all the reversed word
        For i = 0 To arr.GetUpperBound(0)
            strbldr.Append(arr(i))
            strbldr.Append(" ")
        Next

        ' writing to original file
        File.WriteAllText(ofd.FileName, strbldr.ToString())

    End Sub

    ' Reverse Function
    Public Function ReverseString(ByRef strToReverse As String) As String

        Dim result As String = ""

        For i As Integer = 0 To strToReverse.Length - 1

            result += strToReverse(strToReverse.Length - 1 - i)

        Next

        Return result

    End Function

End Class

i hope it helps

It worked, but it doesn't care about dots. :P

teL em wonk fi siht spleh.:D

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim myFile As String = "C:\test.txt" '// your File.
        If IO.File.Exists(myFile) Then '// Check if File.Exists.
            MsgBox(reverseFileContent(myFile)) '// Display Result.
            IO.File.WriteAllText(myFile, reverseFileContent(myFile)) '// Save Reversed File.
        Else : MsgBox("File Does Not Exist.")
        End If
    End Sub

    Function reverseFileContent(ByVal mySelectedFile As String) As String
        Dim arFileLines() As String = IO.File.ReadAllLines(mySelectedFile) '// Load each line as a String Array.
        Dim arWords() As String = Nothing '// used to Split. each line into Words.
        Dim sChar As String = Nothing '// used to get/set last char of word if not a Letter.
        Dim sTemp As String = Nothing '// used to save Reversed Lines.
        For iFileLineNumber As Integer = 0 To arFileLines.Length - 1 '// Loop thru all Lines.
            If arFileLines(iFileLineNumber).Contains(" "c) Then '// Check if Current Line Contains. a "space".
                arWords = arFileLines(iFileLineNumber).Split(" "c) '// Split. Line into Words by "space".
                For iWord As Integer = 0 To arWords.Length - 1  '// Loop thru all Words.
                    If Not arWords(iWord) = Nothing Then '// check if Word is not Nothing, since Words get Split. by " ".
                        If Char.IsLetter(CChar(arWords(iWord).Substring(arWords(iWord).Length - 1, 1))) Then '// check if Last Char is a Letter.
                            arWords(iWord) = StrReverse(arWords(iWord)) '// Reverse the Word.
                        Else '// if Last Char is NOT a Letter.
                            sChar = arWords(iWord).Substring(arWords(iWord).Length - 1, 1) '// get Last Char in Word.
                            '// Reverse Word without the Last Char, then add Last Char back to Word.
                            arWords(iWord) = StrReverse(arWords(iWord).Substring(0, arWords(iWord).Length - 1)) & sChar
                        End If
                        '// Add Reversed Words to String.
                        If Not iWord = arWords.Length - 1 Then : sTemp &= arWords(iWord) & " " '// if Not End of Line, add a "space".
                        Else : sTemp &= arWords(iWord) '// No "space".
                        End If
                    Else '// if Word is Nothing, since Words get Split. by " ", add the "space" back to keep File Format for Line Indenting.
                        sTemp &= " "
                    End If
                Next
            Else '// For Lines that DO NOT Contain Spaces, just a Single Word Line.
                If Not arFileLines(iFileLineNumber) = Nothing Then '// check if Word is not Nothing, since Words get Split. by " ".
                    If Char.IsLetter(CChar(arFileLines(iFileLineNumber).Substring(arFileLines(iFileLineNumber).Length - 1, 1))) Then '// check if Last Char is a Letter.
                        arFileLines(iFileLineNumber) = StrReverse(arFileLines(iFileLineNumber)) '// Reverse the Word.
                    Else '// if Last Char is NOT a Letter.
                        sChar = arFileLines(iFileLineNumber).Substring(arFileLines(iFileLineNumber).Length - 1, 1) '// get Last Char in Word.
                        '// Reverse Word without the Last Char, then add Last Char back to Word.
                        arFileLines(iFileLineNumber) = StrReverse(arFileLines(iFileLineNumber).Substring(0, arFileLines(iFileLineNumber).Length - 1)) & sChar
                    End If
                    sTemp &= arFileLines(iFileLineNumber)  '// Add Reversed Word to String.
                Else '// if Word is Nothing, since Words get Split. by " ", add the "space" back to keep File Format for Line Indenting.
                    sTemp &= " "
                End If
            End If
            If Not iFileLineNumber = arFileLines.Length - 1 Then sTemp &= vbNewLine '// Add Line Breaks if Not Last Line.
        Next
        Return sTemp '// Returns Reversed File Content.
    End Function
End Class

Pretty nice code! Do exactly what I want. I just can't figure now on how to do it using textboxes (:

Btw, talking about text boxes... When I use a simple reversion (each string), if I have more than one line, my output is a single line always. How can I bypass it?

Not quite understanding your question.
..If you need to have a TextBox get reversed as the File does, try this quick fix.

Change this:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim myFile As String = "C:\test.txt" '// your File.
        If IO.File.Exists(myFile) Then '// Check if File.Exists.
            MsgBox(reverseFileContent(myFile)) '// Display Result.
            IO.File.WriteAllText(myFile, reverseFileContent(myFile)) '// Save Reversed File.
        Else : MsgBox("File Does Not Exist.")
        End If
    End Sub

    Function reverseFileContent(ByVal mySelectedFile As String) As String
        Dim arFileLines() As String = IO.File.ReadAllLines(mySelectedFile) '// Load each line as a String Array.
        Dim arWords() As String = Nothing '// used to Split. each line into Words.
        Dim sChar As String = Nothing '// used to get/set last char of word if not a Letter.

To:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        TextBox1.Text = reverseFileContent(TextBox1.Lines)
    End Sub

    Function reverseFileContent(ByVal arFileLines() As String) As String
        '// Load each TextBox Line as a String Array.
        Dim arWords() As String = Nothing '// used to Split. each line into Words.
        Dim sChar As String = Nothing '// used to get/set last char of word if not a Letter.

Not quite understanding your question.
..If you need to have a TextBox get reversed as the File does, try this quick fix.

Change this:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim myFile As String = "C:\test.txt" '// your File.
        If IO.File.Exists(myFile) Then '// Check if File.Exists.
            MsgBox(reverseFileContent(myFile)) '// Display Result.
            IO.File.WriteAllText(myFile, reverseFileContent(myFile)) '// Save Reversed File.
        Else : MsgBox("File Does Not Exist.")
        End If
    End Sub

    Function reverseFileContent(ByVal mySelectedFile As String) As String
        Dim arFileLines() As String = IO.File.ReadAllLines(mySelectedFile) '// Load each line as a String Array.
        Dim arWords() As String = Nothing '// used to Split. each line into Words.
        Dim sChar As String = Nothing '// used to get/set last char of word if not a Letter.

To:

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        TextBox1.Text = reverseFileContent(TextBox1.Lines)
    End Sub

    Function reverseFileContent(ByVal arFileLines() As String) As String
        '// Load each TextBox Line as a String Array.
        Dim arWords() As String = Nothing '// used to Split. each line into Words.
        Dim sChar As String = Nothing '// used to get/set last char of word if not a Letter.

I want both. But, the main interface consists of two text boxes, one with the original text and other with the reversed. I'll Add an checkbox that will active the 'word by word' option, thats why I need it to work with textboxes.

I'll try it, thanks (:

It worked perfect! Thanks!

I'm having a new trouble with it. Here is my code:

Public Class JanelaPrincipal
    Dim TextoOriginal As String = ""
    Dim TextoInvertido As String
    Dim TextoTemporario As String
    Dim S As New SaveFileDialog
    Private Sub InverteTextoOriginal(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles boxTextoOriginal.TextChanged
        If menuLetraPorLetra.Checked = True Then
            TextoOriginal = boxTextoOriginal.Text
            TextoInvertido = StrReverse(TextoOriginal)
            boxTextoInvertido.Text = TextoInvertido
        ElseIf menuPalavraPorPalavra.Checked = True Then
            boxTextoInvertido.Text = reverseFileContent(boxTextoOriginal.Lines)
        End If
    End Sub

    Private Sub InverteTextoInvertido(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles boxTextoInvertido.TextChanged
        If menuLetraPorLetra.Checked = True Then
            TextoOriginal = boxTextoInvertido.Text
            TextoInvertido = StrReverse(TextoOriginal)
            boxTextoOriginal.Text = TextoInvertido
        ElseIf menuPalavraPorPalavra.Checked = True Then
            boxTextoOriginal.Text = reverseFileContent(boxTextoInvertido.Lines)
        End If
    End Sub

    Private Sub TrocaValores(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnInverterValores.Click
        TextoTemporario = boxTextoInvertido.Text
        boxTextoInvertido.Text = boxTextoOriginal.Text
        boxTextoOriginal.Text = TextoTemporario
        TextoTemporario = ""
    End Sub

    Private Sub ExportarTextos(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles menuExportarTextos.Click
        With S
            .Filter = "Texto|*.txt"
            .FileName = "Texto invertido"
        End With

        If S.ShowDialog() = DialogResult.OK Then

            Dim salvar As New System.IO.StreamWriter(S.FileName)
            salvar.Write("Texto original:")
            salvar.WriteLine()
            salvar.WriteLine()
            salvar.Write(boxTextoOriginal.Text)
            salvar.WriteLine()
            salvar.WriteLine()
            salvar.Write("Texto Invertido:")
            salvar.WriteLine()
            salvar.WriteLine()
            salvar.Write(boxTextoInvertido.Text)
            salvar.Close()
        End If
    End Sub

    Private Sub JanelaPrincipal_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Dim myTrackBar As New TrackBar '// Declare New TrackBar.

        With myTrackBar
            .Minimum = 8
            .Maximum = 72
            .TickFrequency = 4
            .BackColor = Color.White
        End With

        AddHandler myTrackBar.Scroll, AddressOf TrackBar_Scroll '// Give it a Event to Handle.
        Dim myCtlHost As New ToolStripControlHost(myTrackBar)
        OpçõesToolStripMenuItem.DropDownItems.Add(myCtlHost) '// Add to Main Menu.

    End Sub
    Private Sub TrackBar_Scroll(ByVal sender As System.Object, ByVal e As System.EventArgs) ' Handles TrackBar1.Scroll

        Dim trk As TrackBar = CType(sender, TrackBar)

        Me.Text = trk.Value.ToString '// For testing.

        boxTextoInvertido.Font = New Font("Lucida Sans Unicode", trk.Value) '// Set Font Name and Size.
        boxTextoOriginal.Font = New Font("Lucida Sans Unicode", trk.Value) '// Set Font Name and Size.
    End Sub

    Function reverseFileContent(ByVal arFileLines() As String) As String
        '// Load each TextBox Line as a String Array.
        Dim arWords() As String = Nothing '// used to Split. each line into Words.
        Dim sChar As String = Nothing '// used to get/set last char of word if not a Letter.
        Dim sTemp As String = Nothing '// used to save Reversed Lines.
        For iFileLineNumber As Integer = 0 To arFileLines.Length - 1 '// Loop thru all Lines.
            If arFileLines(iFileLineNumber).Contains(" "c) Then '// Check if Current Line Contains. a "space".
                arWords = arFileLines(iFileLineNumber).Split(" "c) '// Split. Line into Words by "space".
                For iWord As Integer = 0 To arWords.Length - 1  '// Loop thru all Words.
                    If Not arWords(iWord) = Nothing Then '// check if Word is not Nothing, since Words get Split. by " ".
                        If Char.IsLetter(CChar(arWords(iWord).Substring(arWords(iWord).Length - 1, 1))) Then '// check if Last Char is a Letter.
                            arWords(iWord) = StrReverse(arWords(iWord)) '// Reverse the Word.
                        Else '// if Last Char is NOT a Letter.
                            sChar = arWords(iWord).Substring(arWords(iWord).Length - 1, 1) '// get Last Char in Word.
                            '// Reverse Word without the Last Char, then add Last Char back to Word.
                            arWords(iWord) = StrReverse(arWords(iWord).Substring(0, arWords(iWord).Length - 1)) & sChar
                        End If
                        '// Add Reversed Words to String.
                        If Not iWord = arWords.Length - 1 Then : sTemp &= arWords(iWord) & " " '// if Not End of Line, add a "space".
                        Else : sTemp &= arWords(iWord) '// No "space".
                        End If
                    Else '// if Word is Nothing, since Words get Split. by " ", add the "space" back to keep File Format for Line Indenting.
                        sTemp &= " "
                    End If
                Next
            Else '// For Lines that DO NOT Contain Spaces, just a Single Word Line.
                If Not arFileLines(iFileLineNumber) = Nothing Then '// check if Word is not Nothing, since Words get Split. by " ".
                    If Char.IsLetter(CChar(arFileLines(iFileLineNumber).Substring(arFileLines(iFileLineNumber).Length - 1, 1))) Then '// check if Last Char is a Letter.
                        arFileLines(iFileLineNumber) = StrReverse(arFileLines(iFileLineNumber)) '// Reverse the Word.
                    Else '// if Last Char is NOT a Letter.
                        sChar = arFileLines(iFileLineNumber).Substring(arFileLines(iFileLineNumber).Length - 1, 1) '// get Last Char in Word.
                        '// Reverse Word without the Last Char, then add Last Char back to Word.
                        arFileLines(iFileLineNumber) = StrReverse(arFileLines(iFileLineNumber).Substring(0, arFileLines(iFileLineNumber).Length - 1)) & sChar
                    End If
                    sTemp &= arFileLines(iFileLineNumber)  '// Add Reversed Word to String.
                Else '// if Word is Nothing, since Words get Split. by " ", add the "space" back to keep File Format for Line Indenting.
                    sTemp &= " "
                End If
            End If
            If Not iFileLineNumber = arFileLines.Length - 1 Then sTemp &= vbNewLine '// Add Line Breaks if Not Last Line.
        Next
        Return sTemp '// Returns Reversed File Content.
    End Function

End Class

Whenever I choose the 'word by word' option, and write a word, as soon as a write a space, my app hangs, and doesn't even give me a error. What I've did wrong?

Nevermind, I found it. I was doing the reversions on both textboxes at the same time.

:D
I'm sure such happens even to the best of us. It's part of being "human".