(newbie) - reading data from a file - in VB 2005 EE

  • Thread starter Thread starter Opa Vito
  • Start date Start date
O

Opa Vito

Hello, I need to read data from a file the old fashioned way, more or
less like in the old days when ini files were used. But to be honest, I
can't find anything in the documentations (I'm not English, maybe I just
don't understand it).

Let's assume I have this in the file (called setup.txt):

[settings]
name1=Vito
name2=Doortje
txt1=married with children
txt2=and still happy
pic=both.jpg

My program must read this content and assign the data in the rigth hand
portion to a variable (declared public)with the name of the left hand
portion of each line, and above all the program must search ONLY in the
[settings] section ( there will be other additional sections in the future)

All tips very welcome, please understand I'm a newbie at programming in
VB and I'm not English ...

Many thanks

Vito
 
Hi Opa,

Do you absolutely have to use that file format? Because if you are free
to choose the format of the settings file, you'd be a lot better off
using an xml file.

If you are stuck using that file format you will need to do the
following - I'm not going to come up with the vb.net code for you
because i'm too lazy but you will have fun working it out I'm sure :)

- Open a Stream object on the file.
- Open a StreamReader on the Stream.

- Start a loop, calling StreamReader.ReadLine each time.
- Continue the loop until the line read was "[settings]" then exit the
loop.

- Start a new loop, calling StreamReader.ReadLine each time.
- Within the loop, get the lefthand side by using string.substring(0,
string.indexof("="))
- Do a select case statement on the lefthand side
- have case statements for each entry under "[settings]" which do the
assigning of the value
- Continue the loop until the line read begins with "[".

Apologies if I've got anything wrong, I'm just doing this off the top
of my head. It should be enough to get you started though, come back if
you have any problems :)

Phil
 
You need to use the Filestream and streamreader (readline) classes. Then
use string functions to parse each line (using the "=" as the delimiter).
 
(e-mail address removed) schreef:
Hi Opa,
Click to expand...

Hey Phil,
Do you absolutely have to use that file format? Because if you are free
to choose the format of the settings file, you'd be a lot better off
using an xml file.
Click to expand...

I expect a lot of people of our 'secret community' will use this program
if I ever can make it run the way it's intended, and I'm sure it will be
much more easy for most of them to edit a simple text file rather than a
XML .. Of course this setup file is the smallest of maybe 4 or 5 other
files that has to be read the same way ... But I will take a look at XML
too.
If you are stuck using that file format you will need to do the
following - I'm not going to come up with the vb.net code for you
because i'm too lazy but you will have fun working it out I'm sure :)
Click to expand...
<snip>

No problem, I believe I understand your explanation, with a bit of
search I must find out what code to use.

Thanks for your cooperation

Vito
 
Hi, I'm stuck :-)

This the class I use to read the data:

Imports System
Imports System.IO
Class Class1
Public Shared Sub ReadGeneral()
Try
Using sr As StreamReader = New StreamReader("c:\general.txt")
Dim line As String
Dim element As String

Do
line = sr.ReadLine()
Loop Until line = "[general]"

Do
line = sr.ReadLine()

element = line.Substring(0, line.IndexOf("="))

Form1.TextBox1.Text = Form1.TextBox1.Text &
element_ & vbCrLf

Loop Until line Is Nothing

sr.Close()
End Using
Catch E As Exception

Form1.TextBox1.Text = E.Message

End Try
End Sub
End Class

Of course I first write to the textbox to see if everything is OK .. but
I have an error report saying:
"object reference not set to an instance of an object"

It's the "element = line.Substring(0, line.IndexOf("="))" that makes it
go wrong, but I have no idea whatsoever what can be done about it ...

Any help?
Thanks

Opa Vito
 
Hello Opa,

String manipulation (at least the limited and incorrect varienty offered
in the previous postings) is not the answer. Win32 already provides this
functionality (which you can easily wrap up in a class lib) in the form of
GetPrivateProfileString (in kernel32.dll) and it's cohorts.

-Boo
 
GhostInAK schreef:
Hello Opa,

String manipulation (at least the limited and incorrect varienty offered
in the previous postings) is not the answer. Win32 already provides
this functionality (which you can easily wrap up in a class lib) in the
form of GetPrivateProfileString (in kernel32.dll) and it's cohorts.

-Boo
Click to expand...

Oops ... being a newbie, this sounds Chinese to me :-)
Can you please give me some more info or maybe a bit code to start with?
No need for fully functional code (however, if possible, that would be
great too), but just something to get started ...

Thanks

Opa Vito
 
Opa Vito schreef:
Hi, I'm stuck :-)
Click to expand...

I found it ... after trying for at least 5 hours ... :-)
just had to insert this:

If line IsNot Nothing Then 'SOLUTION
element = line.Substring(0, line.IndexOf("="))
Form1.TextBox1.Text = Form1.TextBox1.Text & element & vbCrLf
End If

So checking if the line wasn't empty before looking for the substring ..

Vito
 
Opa said:
GhostInAK schreef:

Oops ... being a newbie, this sounds Chinese to me :-)
Can you please give me some more info or maybe a bit code to start with?
No need for fully functional code (however, if possible, that would be
great too), but just something to get started ...
Click to expand...

Go to www.pinvoke.net and look up the GetPrivateProfileString and
SetPrivateProfileString functions for further information on these
functions, but here is the VB example they listed (adjusted to match
your file):

Imports System.Runtime.InteropServices
Imports System.Text
Module1
Private Declare Auto Function GetPrivateProfileString Lib
"kernel32" (ByVal lpAppName As String, _
ByVal lpKeyName As String, _
ByVal lpDefault As String, _
ByVal lpReturnedString As StringBuilder, _
ByVal nSize As Integer, _
ByVal lpFileName As String) As Integer

Sub Main()

Dim res As String
Dim sb As StringBuilder

sb = New StringBuilder(500)
res = GetPrivateProfileString("settings", "name1", "", sb,
sb.Capacity, "c:\test.ini")
Console.WriteLine("GetPrivateProfileStirng returned : " & res)
Console.WriteLine("KeyName is : " & sb.ToString())

End Sub
End Module
 
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