[RESOLVED] Read certain Lines from .txt file

[Alexandru_mbm]

For the moment i use this code wich is reading only one line at time:

        Dim Tr As IO.TextReader = System.IO.File.OpenText(My.Settings.masuratori_preluare_date)
        Dim TW As System.IO.TextWriter
        Dim nume_fisier As String

        Dim MyFileLine As String = Split(Tr.ReadToEnd(), vbCrLf)(6) & vbCrLf

        nume_fisier = My.Settings.masuratori_salvare_date & Format(Date.Now.Day) & "-" & Format(Date.Now.Month) & "-" & Format(Date.Now.Year) & " la " & Format(Date.Now.Hour) & "." & Format(Date.Now.Minute) & "." & Format(Date.Now.Second) & "s" & ".txt"

        Tr.Close()

        TW = System.IO.File.CreateText(nume_fisier)
        TW.WriteLine(MyFileLine)
        'Write another line 
        'TW.WriteLine("Hello World Again")
        TW.Flush()
        TW.Close()

How can i do if i want to read more than one specific line ?!

Thanks in advice!

[jmcilhinney]

You're reading the file and splitting it into lines, but then you only get one of those lines and throw the rest away. How about you keep all the lines. Then you can access any one you want any time. There's a far more elegant way to get the lines too:

Dim lines As String() = IO.File.ReadAllLines("file path here")

Now you can access any line you want from the 'lines' array at your leisure.

EDIT: Thanks stanav, but I might have to rep you down for finding fault in my post.

[stanav]

Just a minor correction on JMC's code. It should be this

Dim lines() As String = IO.File.ReadAllLines("file path here")

'Or this

Dim lines As String() = IO.File.ReadAllLines("file path here")

[Alexandru_mbm]

I have put your code but in the text file is showing me "System.String[]"

        Dim Tr As IO.TextReader = System.IO.File.OpenText(My.Settings.masuratori_preluare_date)
        Dim TW As System.IO.TextWriter
        Dim nume_fisier As String

        'Dim MyFileLine As String = Split(Tr.ReadToEnd(), vbCrLf)(1) & vbCrLf

        Dim MyFileLines As String() = IO.File.ReadAllLines(My.Settings.masuratori_preluare_date)

        nume_fisier = My.Settings.masuratori_salvare_date & Format(Date.Now.Day) & "-" & Format(Date.Now.Month) & "-" & Format(Date.Now.Year) & " la " & Format(Date.Now.Hour) & "." & Format(Date.Now.Minute) & "." & Format(Date.Now.Second) & "s" & ".txt"

        Tr.Close()

        TW = System.IO.File.CreateText(nume_fisier)
        TW.WriteLine(MyFileLines)
        TW.Flush()
        TW.Close()

[ProphetBeal]

You have to join the array before you can write it to the file.

TW.WriteLine(String.Join(ControlChars.CrLf, MyFileLines))

[Alexandru_mbm]

But my problem is still not solved!

How can i read for example only line 4 and 6 from that text file ?

Thanks again for your big help!

[stanav]

We showed you how to read the contents of a file into a string array where each element holds a line of your text. Now if you want to read a specific line, you just read it from the array at a specific index. Arrays are zero based, so for example, if you want line#3 in your text file, you will read the array element at index#2.

 
Dim lines As String() = IO.File.ReadAllLines("path here")
Dim line3 As String = lines(2)

One thing you have to keep in mind that if you're trying to access an element that is not in the array, you program will crap out.

[Alexandru_mbm]

Working...

Thanks alot for your big help!

[abu abdellah]

thank you all guys for helping me also.