[RESOLVED] could it be better

[user name]

i have changed an old vb6 application to 2005.net and i want to know if this sub (which does work) could be better, by that i mean have i used the right functions ?, are there better(faster) ones ?

this removes a username and every line under it until it reaches another username.

Public Sub RemoveUser(ByVal StringUser As String)
        Dim sr As New IO.StreamReader("C:\usernamesinfo.txt")
        Dim sw As New IO.StreamWriter("C:\usernamesinfo2.txt", True)
        Dim Found As Boolean, Lines As String
 
        Do While sr.Peek >= 0
            Lines = sr.ReadLine
 
            If Found = False Then
                If InStr(Lines, "USERNAME" & StringUser) = 0 Then
                    sw.WriteLine(Lines)
                Else
                    Found = True
                End If
            Else
                If InStr(Lines, "USERNAME") > 0 Then
                    Found = False
                    sw.WriteLine(Lines)
                End If
            End If
        Loop
        sr.Close()
        sw.Close()
        IO.File.Delete("C:\usernamesinfo.txt")
        IO.File.Move("C:\usernamesinfo2.txt", "C:\usernamesinfo.txt")
 
    End Sub

thanks.

[dinosaur_uk]

Public Sub RemoveUser(ByVal StringUser As String)
        Dim sr As New IO.StreamReader("C:\usernamesinfo.txt")
        Dim sw As StreamWriter
        Dim al As New ArrayList
        Dim i As Integer
 
        Dim str As String
        Dim arrTemp() As String
        Dim Basket As New ArrayList
 
        str = sr.ReadToEnd
        sr.DiscardBufferedData()
        sr.Close()
        IO.File.Delete("C:\usernamesinfo.txt")
        sw = IO.File.CreateText("C:\usernamesinfo.txt")
 
        arrTemp = str.Split("USERNAME")
 
        For i = 0 To arrTemp.Length - 1
            If arrTemp(i).ToString.StartsWith(StringUser) Then
                'Do nothing, this effectively removes it
            Else
                Basket.Add(arrTemp(i).ToString)
            End If
        Next
 
        For i = 0 To Basket.Count - 1
            sw.WriteLine("USERNAME" & Basket(i).ToString)
        Next
        sw.Flush()
        sw.Close()
    End Sub

Haven't tried it out ....but here it goes..

[user name]

thanks for your reply. its not exactly what i wanted but that s my fault for not showing a typical example of the file but on the other hand you have shown me a few more functions that i didnt know existed.

thank you very much.

[dinosaur_uk]

no problems

could you explain what you are trying to do in greater detail?

[jmcilhinney]

dinosaur_uk, note that the String.Split method cannot split on a substring, but only a single character. If you pass a string as the argument with Option Strict turned Off it will be implicitly converted to a character by taking just the first character. If Option Strict is turned On the code will not compile. There is an overload that takes an array of characters, but that splits on every instance of any one of those characters. You would need to use either the Split Runtime function or the Regex.Split method.

I would recommend against using a second file. Unless the file is really large, I would reas it like this:

Dim lines As String() = System.Text.RegularExpressions.Regex(myStreamReader.ReadToEnd(), Environment.NewLine)

If you really must use a second file, you should use the System.IO.Path.GetTempFile method to create a genuine temp file.

Once you have the lines of the file in the array, you can just loop over those strings and either edit them directly, or write them back to the same file name. Finally, use the String.IndexOf method instead of InStr. InStr is a Runtime function that would implicitly call String.IndexOf anyway, so why add the extar layer?

[dinosaur_uk]

Ok ...cheers...didnt know that...

[user name]

with the suggestions of some functions and methods i have changed it all to this.

Public Sub RemoveUser(ByVal StringUser As String)
        Dim sa As New ArrayList(IO.File.ReadAllLines("C:\usernamesinfo.txt"))
        Dim start As Int16 = sa.IndexOf("USERNAME" & StringUser)
        Dim i As Int16, counter As Int16
 
        For i = start + 1 To sa.Count - 1
            If sa(i).ToString.StartsWith("USERNAME") Then
                Exit For
            Else
                counter += 1
            End If
        Next
 
        sa.RemoveRange(start, counter + 1)
 
        IO.File.WriteAllLines("C:\usernamesinfo.txt", sa.ToArray(GetType(String)))
    End Sub

thanks for the direction.

[dinosaur_uk]

nice