My own file format, Need help[soLVEd]

[scr0p]

I am trying to make a file format so I can better my self at binary file access. The extension is *.tits and it holds a name, age and comments. This is the code:

I want to check if the file exists, the function I made isnt working, "FilesHere", Can someone tell me whats wrong with it.

Problems:

When I save the file, it makes example.tits but if I open it in notepad I can see the comments and name, I know its because they are string but is there anyway to hide that.

When loading, I get the name back but age is 0 and I get like half of the comments.

Option Explicit
Dim VersionCheck As Integer
Dim nLen As Integer, nLen2 As Integer
Private Type TITS
    Name As String
    Age As Byte
    Comments As String
End Type
Dim TheAge As Byte
 
Private Sub Command1_Click()
CommonDialog1.Filter = "T i T S (*.tits)|*.tits"
CommonDialog1.ShowOpen
End Sub
 
Private Sub Command2_Click()
Dim ageX As Byte
Dim CommentsX As String, NameX As String
    If FilesHere(Text1.Text) Then
        Open Text1.Text For Binary Access Read Lock Write As #1
            Get #1, , VersionCheck
            If VersionCheck <> 6 Then MsgBox ("Not made in TFV 6")
            Get #1, , nLen
            NameX = Space(nLen)
            Get #1, , NameX
            Get #1, , nLen2
             CommentsX = Space(nLen2)
            Get #1, , nLen2
            Get #1, , CommentsX
            Get #1, , ageX
        Close #1
        Text2.Text = CommentsX
        Text4.Text = ageX
        Text3.Text = NameX
    Else
        MsgBox ("File not found, dummy!"), , "Where"
    End If
    
End Sub
 
Private Sub Command3_Click()
TheAge = Val(Text4.Text)
 
Dim MyFile() As TITS
    'If FilesHere(Text1.Text) Then
    '    If UCase(Right(Text1.Text, 4)) = "TITS" Then Kill Text1.Text
   ' End If
        Open Text1.Text For Binary Access Write Lock Read Write As #1
            Put #1, , VersionCheck
            nLen = Len(Text3.Text)
            Put #1, , nLen
            Put #1, , Text3.Text
            nLen2 = Len(Text2.Text)
            Put #1, , nLen2
            Put #1, , Text2.Text
            Put #1, , TheAge
        Close #1
End Sub
 
Private Sub Form_Load()
VersionCheck = 6
    Text1.Text = App.Path & "\Example.tits"
End Sub
 
Private Function FilesHere(TheFileName As String) As Boolean
    If FileLen(TheFileName) > 0 Then
        FilesHere = True: Exit Function
    Else
        FilesHere = False: Exit Function
    End If
End Function

[scr0p]

I think I fixed it. I changed byte to integer, (Can I use LONG instead?) and I took out an extra line for reading comments that was there by accident.

[Valkan]

you can use any data type you want in your file. The data type is just a way of knowing how much byte you put in the file. What is important is if you put a long at position 300 in your file, to get this value back, you must get a long at position 300, if you use a shorter variable, you will miss some data and if you use a bigger variable, you will get to much byte and the result won't seem accurate.

[scr0p]

How do I put it at position 300? If I am just storing lets say an age, can I use a byte? If I am storing the size of a file in bytes, can I use long? etc, and do I just change dim XXX as byte to dim XXX as long. Also If I make a file with strings, does the length HAVE to be right before the string itself?

[Valkan]

300 was just an exemple, i don't know if you can put data at a precise point in a file if data as not been put before that part. But you can get to position 300 (if there is a value) by using the seek method

Seek #NumFile,,300

This would move the file pointer to... well 300

If I am just storing lets say an age, can I use a byte?

Well... unless your storing the age of something that can be older than 255, of course you can. But, if you put the age in your file using a byte, you must read the age from the file using a byte variable. That's what i've tried to explain in my previous post.

If I am storing the size of a file in bytes, can I use long?

you can use any data type that will be able to hold the numeric value of the file size. The numeric value will represent the file size in byte... you don't need to use a byte variable just because you saving value that represent a number of bytes.

Also If I make a file with strings, does the length HAVE to be right before the string itself?

If you save a string to a binary file, you should save the len of the string also so you can size a string variable correctly to get the right amount of data from the file when you try to read your string. (what you already seem to do from the look of your code)

and for a closing gift : http://rookscape.com/vbgaming/tutS.php this should help you alot to understand how binary files work.

- Good luck
- Valkan