[RESOLVED] Extra newline chars on file append

[Brian M.]

Hello. I am writing a program that will read and write to a file using the My.Computer.Filesystem namespace, and when I append my data file with the code shown below under SaveFile subroutine, it sometimes places extra ControlChars.Newline at the end of the appended text. Sometimes it places one extra newline, and sometimes it adds 3-6 newlines. I have tried everything I can think of to make it add just one newline at the end of each append, as I will be using the newline char to flag each entry on retrieval. I am working out some algorithms in this project to use in a project that will keep track of data in a file using csv format(just practicing saving/retrieving data from a file). The extra newline characters that are added will become a problem when I start to sort the data to display. Any help will be appreciated.

my xSaveButton click event:

   Private Sub xSaveButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles xSaveButton.Click

        Dim boolAppendData As Boolean

        If My.Computer.FileSystem.FileExists("myData.dat") = True Then
            Dim overWrite As String = MsgBox("Overwrite data file? Selecting yes will overwrite" & vbCrLf & _
            "the data file. Selecting no will append to it.", MsgBoxStyle.YesNo, "Data File")

            If overWrite = DialogResult.Yes Then
                boolAppendData = False
            Else
                boolAppendData = True
            End If

            SaveFile(boolAppendData)
        Else
            SaveFile(False)
        End If

      End Sub

my save subroutine:

Private Sub SaveFile(ByVal boolAppend As Boolean)

        If Me.xTextBox.Text = String.Empty Then
            MsgBox("There is nothing to save to the file." & vbCrLf & "Type something in the textbox " _
            & vbCrLf & "or open a file first.", MsgBoxStyle.OkOnly, "Empty Textbox")
        Else
            Try
                My.Computer.FileSystem.WriteAllText("myData.dat", Me.xTextBox.Text & ControlChars.NewLine, boolAppend)
                MsgBox("File saved successfully.", MsgBoxStyle.OkOnly, "File Saved")
            Catch ex As Exception
                MsgBox("There was a problem saving the file." & vbCrLf & ex.ToString, MsgBoxStyle.OkOnly, "File Not Saved")
            End Try
        End If

End Sub

[Shaggy Hiker]

Can you confirm that the newline characters are not already there before you append your text?

[Brian M.]

Yes. I have went so far as to format the text file by hand first. And when appending to the file, I have made sure the cursor was on the same line as the last line of text to be appended before I click the save button. And it doesn't happen all the time either. It acts like it keeps a count and increments the newline character by one each time I append it. So first time it works fine, the next time there is one extra newline, then two, ect.

[dcrew]

1] Dont use 'ControlChars.NewLine' use 'Environment.NewLine' it is less buggy and more secure as i figured back when i had a problem like this.

2] Code:

Public Function RemoveNewlinesAtEnd(Dim Text As String) As Single
     If Text.EndsWith(Environment.Newline) Then
          Text = Text.Substring(0, Text.Length - Environment.Newline)
     End If
End Function

TextBox1.Text = RemoveNewlinesAtEnd(TextBox1.Text)

I have not tested it but if you get an error change the:

Text = Text.Substring(0, Text.Length - Environment.Newline)

to

Text = Text.Substring(0, Text.Length - 1)

[Brian M.]

Your implementation is pretty much what I had in mind for reading in the values from the file. Except I will be using indexOf to get the newline position, then subtracting it from a variable that stores the first position of the character right after the preceding newline, thereby placing each 'line' into a string array. I replaced the controlchars.newline with the environment.newline, and it seems to have stopped adding the random newlines to my appends. Thanks for that.

[Philly0494]

nevermind, it has been resolved

[Brian M.]

Tanks anyways philly. But if you have another suggestion, I will be glad to hear it. There is always more than one way to skin a cat.

[EntityX]

I recently ran into a similar problem. What I noticed is that if I processed the string so that it was just digits with the return characters and I tested the string with IsNumeric it said it was numeric even though return characters were in there. I wanted a number in the final string so after processing the string to get the digits and the return character I converted to decimal :

adec = CDec(st1)  ' st1 is the string  and adec is declared as decimal

and then put adec back in the string and that way got rid of the return characters. When I had processed the string for instance if my result was 10 and I asked for the length of the string it said 4 so it had two return characters in there. I tried

        If st1.IndexOf(Chr(13)) <> -1 Then
            st1.Replace(Chr(13), "")
        End If
        If st1.IndexOf(Chr(10)) <> -1 Then
            st1.Replace(Chr(10), "")
        End If

but it didn't strip out the return. What I found just now is that I could remove the return from the string by using remove. I got the length of the string and removed the 2 characters whatever they were and that way is another way I could get rid of the return. So if you properly process the string you can remove the line return using remove.

Here's some code that worked in my situation. Maybe you could use IsLetterOrDigit instead of IsNumeric.

        st1L = st1.Length
        a1 = 0
        If st1L > 0 Then
            For i = 0 To st1L - 1
                If IsNumeric(st1.Substring(i, 1)) = False Then
                    a1 += 1
                End If
            Next
            If a1 > 0 Then
                st1 = st1.Remove(st1L - a1, a1)
            End If
        End If

[Brian M.]

Well maybe in your code where you look for chr(13), you could instead look for controlchars.newline or environment.newline instead of converting 13 to its ascii value. Maybe that will be a bit cleaner. But thanks for the suggestion. Need a string.trimNewline
function, hehe.

[dcrew]

Good Working and Helping also Resloving your problem for you! Anymore questions or code you need then PM me or post a new topic.