VB - Save/Load settings to/from file

[frozen]

With this class you can Save your programs settings to a file, and load it on startup. It uses a PropertyBag for its saving and loading because if its .Contents property. This class was inspired by CVMichael.

Add a new class module to your project, name it CSettings and add the following code to it

Option Explicit
 
' CSettings 1/27/2006
 
Private Keys() As String
Private Vals() As String
Private Settings As Integer
 
Private Sub Class_Initialize()
    Settings = -1
End Sub
 
Private Function IsSet(ByVal Key As String) As Integer
    Dim i As Integer
    If Settings <> -1 Then
        For i = 0 To Settings
            If Keys(i) = Key Then
                IsSet = i
                Exit Function
            End If
        Next
    End If
    IsSet = -1
End Function
 
Public Sub Save(ByVal Key As String, ByVal Val As String)
    Dim i As Integer
    i = IsSet(Key)
    If i = -1 Then
        Settings = Settings + 1
        ReDim Preserve Keys(Settings)
        ReDim Preserve Vals(Settings)
        Keys(Settings) = Key
        Vals(Settings) = Val
    Else
        Vals(i) = Val
    End If
End Sub
 
Public Function Load(ByVal Key As String) As String
    Dim i As Integer
    i = IsSet(Key)
    If i = -1 Then
        Load = ""
    Else
        Load = Vals(i)
    End If
End Function
 
Public Sub SaveToFile(ByVal Filename As String)
    Dim PB As New PropertyBag
    Dim i As Integer
    Dim Binary() As Byte
    If Len(Dir(Filename)) <> 0 Then
        DeleteFile Filename
    End If
    PB.WriteProperty "s", Settings
    For i = 0 To Settings
        PB.WriteProperty "k" & i, Keys(i)
        PB.WriteProperty "v" & i, Vals(i)
    Next
    i = FreeFile
    Open Filename For Binary As i
        Binary = PB.Contents
        Put i, , Binary
        Erase Binary
    Close i
End Sub
 
Public Sub LoadFromFile(ByVal Filename As String)
    Dim PB As New PropertyBag
    Dim i As Integer
    Dim Binary() As Byte
    i = FreeFile
    Open Filename For Binary As i
        ReDim Binary(LOF(i))
        Get i, , Binary
        PB.Contents = Binary
        Erase Binary
    Close i
    Erase Keys
    Erase Vals
    Settings = Int(PB.ReadProperty("s"))
    For i = 0 To Settings
        ReDim Preserve Keys(i)
        ReDim Preserve Vals(i)
        Keys(i) = PB.ReadProperty("k" & i)
        Vals(i) = PB.ReadProperty("v" & i)
    Next
End Sub

Example usage:

Dim Settings As New CSettings
Sub Form_Load()
    If Len(Dir(App.Path & "\Settings.bin")) <> 0 Then
        Settings.LoadFromFile App.Path & "\Settings.bin"
    Else
        Settings.Save "Started", 0
    End If
    Settings.Save "Started", Settings.Load("Started") + 1
End Sub
 
Sub Form_Unload()
    Settings.SaveToFile App.Path & "\Settings.bin"
End Sub

[CVMichael]

First of all, thanks for giving me credit also.

Now about why I posted:
In the SaveToFile sub, you have DeleteFile wich is not a VB keyword (maybe your using API for that ?), well I think it should be "Kill FileName"

Second problem:
It gives error when I copy & paste this code:

Sub Form_Unload()
    Settings.SaveToFile App.Path & "\Settings.bin"
End Sub
 
' it should be:
[b]Private Sub Form_Unload(Cancel As Integer)[/b]
    Settings.SaveToFile App.Path & "\Settings.bin"
End Sub

And a note to add to the original idea:
One nice thing about this method of saving your settings is that you can easily encrypt all the data in the PropertyBag before you save the data, and decrypt when you load the data.
(Instead of encrypting each value one by one)

[Edit]
I also use this method (using the PropertyBag.Contents Property) to easily send settings/data over a winsock connection. Makes things a little easier.

[nicodemusashes]

this is exactly what i'm looking for, i have to save an option that is either on or off, but i want my program to retrieve that option when it is closed and re-opened, but i have no idea how i would utilize the code you have provided

hope you can help

[Mark Gambo]

Why not just save the settings to the registry as long as the users have permission to do so.

[nicodemusashes]

thats a good idea, how to i read and right from the registry lol

[CVMichael]

thats a good idea, how to i read and right from the registry lol

Use SaveSetting and GetSetting

[nicodemusashes]

sorry, but i've never worked with registry settings before, how exactly would i do that?

[CVMichael]

sorry, but i've never worked with registry settings before, how exactly would i do that?

It's not rocket science.... really....

Just type "SaveSetting" in VB, then press F1

Or use Google, this is the first link on Google that I found by searching for SaveSetting, and it happes to be right in our own forum !
http://www.vbforums.com/showthread.php?t=232113

If you don't know something, do a search, it's much faster than waiting for us to respond on the forums, right ?
And if you can't find anything by searching, then post the question, otherwise we will search for your question, and post the links like I just did... what's the point of that ?