Visual Basic

Open OutputFile                                   'Using sw As StreamWriter
   Open InputFile                                 'Using sa As StreamReader
      Copy InputFile to CpyFile                   'i.e. to Similar1.txt
      Read InputFile into temp                    '1st header
      Set up p() array from temp
      Read InputFile into temp                    '2nd header
      While not at end of InputFile
         Read InputFile into temp                 'Data line
         Split temp                               'Into name, child, etc
         Open CpyFile                             'Using sa1 As StreamReader
            Read CpyFile into temp1               '1st header
            Set up p() array from temp            'Why? This has already been done
            Split temp1                           'Into name1, child1, etc
            Write Name1, child1, etc to OutFile   '1st header. Why not just write temp1 without splitting?
            Read and Write from CpyFile           '2nd header
            While not at end of CpyFile
               Read CpyFile into temp1            'Data line
               If (temp matches temp1) and created < created1 Then
                  Write temp1 to OutFile
               Else
                  Write temp to OutFile
               End If
            End While  'not EOF CpyFile
         Close CpyFile 'End Using
      End While 'not EOF InputFile
   Close InputFile 'End Using
Close OutPutFile 'End Using

Using sw As StreamWriter = New StreamWriter(oFile, False, System.Text.Encoding.Default)
    Using sa As StreamReader = New StreamReader(iFile, System.Text.Encoding.Default)
        File.Copy(iFile, "c:\DB\Output1\Similar1.txt", True)
        temp = sa.ReadLine()
        ....
        sw.WriteLine(sa.ReadLine())

        While sa.Peek() >= 0
            temp = sa.ReadLine()
            ....
            If Trim(name).Substring(0, 2) = "01" Then
                sw.WriteLine(name & child & desF & desAF & desA & desAA & ecn & dnf & baloon & dateTime & qty)
            Else
                Dim foundLaterMatch As Boolean = False
                Using sa1 As StreamReader = New StreamReader("c:\DB\Output1\Similar1.txt", System.Text.Encoding.Default)
                    sa1.ReadLine()
                    sa1.ReadLine()

                    While (sa1.Peek() >= 0 ) AndAlso (Not foundLaterMatch)
                        temp1 = sa1.ReadLine()
                        .....
                        If name = name1 And child = child1 And dnf = dnf1 And baloon = baloon1 And result < 0 Then
                            foundLaterMatch = True
                        End If
                    End While
                End Using
                If Not foundLaterMatch Then
                    sw.WriteLine(currentLine)
                End If
            End If
        End While
    End Using
End Using

If Not IO.directory.exists("C:\Backup") Then
IO.Directory.Create("C:\Backup")
End If

Dim a As String = "C:\Myproject\bin\debug\my.mdf"
Dim d As String = "C:\Backup\my.mdf"
IO.File.Copy(a,d)
MsgBox("Backup of 'my.mdf' was succesfull.")