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Find number of elements and its size Vb.net RRS feed

  • Question

  • Hi,

    we are trying to read a .dat file which is saved using VB6 random file mode. Each Record Size is 169, Which is further divided into 29 sub values And are success full in reading 4 values out of these 29 values.

    is there any tools which can help find the size of data in each element so that it will be possible to retrieve all the values ?

    Below is the code with which we were able to retrieve few data. Its a Sample code to identify where the variables are

    Module Module1
        Structure new_type_spice
            <VBFixedString(5)> Dim Var0 As String  'Variable size 5
            <VBFixedString(30)> Dim Var1 As String 'Variable size 30
            Dim Var2 As Long
            Dim Var3 As Long
            Dim Var4 As Long
            Dim Var5 As Long
            Dim Var6 As Long
            Dim Var7 As Long
            Dim Var8 As Long
            Dim Var9 As Long
            <VBFixedString(2)> Dim Var10 As String
            <VBFixedString(12)> Dim Var11 As String '68 length from var1 to var11 and variable size of 12
            <VBFixedString(1)> Dim Var12 As String
            <VBFixedString(1)> Dim Var13 As String
            <VBFixedString(1)> Dim Var14 As String
            <VBFixedString(1)> Dim Var15 As String
            <VBFixedString(1)> Dim Var16 As String
            <VBFixedString(1)> Dim Var17 As String
            <VBFixedString(1)> Dim Var18 As String
            <VBFixedString(1)> Dim Var19 As String
            <VBFixedString(1)> Dim Var20 As String
            <VBFixedString(1)> Dim Var21 As String
            <VBFixedString(1)> Dim Var22 As String
            <VBFixedString(1)> Dim Var23 As String
            <VBFixedString(1)> Dim Var24 As String
            <VBFixedString(1)> Dim Var25 As String
            <VBFixedString(1)> Dim Var26 As String
            <VBFixedString(1)> Dim Var27 As String
            <VBFixedString(40)> Dim Var28 As String  'Variable size of 40
        End Structure
    End Module
    

    Public Class Form1
        Dim table1 As DataTable
        Dim source_file As String = "C:\Users\Developer\Desktop\Speiseliste\Speisen.dat"
        Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
            Dim rec As New new_type_spice, Count As Integer
            If Len(rec) <> 169 Then
                Dim ans = MsgBox("Length of datatype is : " & Len(rec), vbYesNo)
                If ans = vbYes Then Exit Sub
                If ans = vbNo Then Exit Sub
            End If
            Dim FileNum = FreeFile()
            FileOpen(FileNum, source_file, OpenMode.Random, , , 169)
            Count = 1
            Do While Not EOF(FileNum)
                'Read the record on the position Count.
                FileGet(FileNum, rec, Count)
                Dim row As DataRow = table1.NewRow
                row(0) = rec.Var0
                row(1) = rec.Var1
                row(2) = rec.Var2
                row(3) = rec.Var3
                row(4) = rec.Var4
                row(5) = rec.Var5
                row(6) = rec.Var6
                row(7) = rec.Var7
                row(8) = rec.Var8
                row(9) = rec.Var9
                row(10) = rec.Var10
                row(11) = rec.Var11
                row(12) = rec.Var12
                row(13) = rec.Var13
                row(14) = rec.Var14
                row(15) = rec.Var15
                row(16) = rec.Var16
                row(17) = rec.Var17
                row(18) = rec.Var18
                row(19) = rec.Var19
                row(20) = rec.Var20
                row(21) = rec.Var21
                row(22) = rec.Var22
                row(23) = rec.Var23
                row(24) = rec.Var24
                row(25) = rec.Var25
                row(26) = rec.Var26
                row(27) = rec.Var27
                row(28) = rec.Var28
                table1.Rows.Add(row)
                table1.AcceptChanges()
                dg.Refresh()
                Count = Count + 1
            Loop
            FileClose(FileNum)
        End Sub
    
        Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
            table1 = New DataTable("Test_Table")
            Dim column As New DataColumn
            For i = 0 To 28
                Dim column1 As DataColumn = New DataColumn("Column " & i)
                table1.Columns.Add(column1)
            Next
            dg.DataSource = table1
            Button2_Click(sender, e)
        End Sub
    End Class
    

    below is the screenshot from Hex Editor Application.

    here is the .dat file we are trying to access. 1Speisen.dat


    Coderv9

    Friday, May 31, 2019 9:56 PM

Answers

All replies

  • If you're asking a VB.Net question I'd ask for help over here.

    https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?forum=vbgeneral

    otherwise if this is about VB6 then the microsoft forums are long gone so try here or also others you can search for.

    http://www.vbforums.com/forumdisplay.php?1-Visual-Basic-6-and-Earlier

     

     



    Regards, Dave Patrick ....
    Microsoft Certified Professional
    Microsoft MVP [Windows Server] Datacenter Management

    Disclaimer: This posting is provided "AS IS" with no warranties or guarantees, and confers no rights.

    Friday, May 31, 2019 11:16 PM
    Moderator

  • is there any tools which can help find the size of data in each element 

    Variables appear to be fixed size and most of the file is just binary zeroes. (Using Notepad++ hex editor)

     

    $data = Get-Content C:\users\dave\Downloads\1Speisen.dat
    $pos = 0
    while($pos -lt $data.Length)
    {
        $rec = $data.Substring($pos,169)
        $menuitem = $rec.Substring(5,30)    
        $not = $rec.Substring(103,12)
        "$menuitem $not"
        $pos += 169
    }

    Saturday, June 1, 2019 2:17 AM
  • HI Dave,

    We are looking for a solution in VB.net.


    Coderv9

    Saturday, June 1, 2019 6:21 AM
  • Hi MotoX80,

    Thank you for inputs. But the strange part is there are actual data in those field. This is the screenshot from the app that reads this file. It's quite outdated and we wanted to move all the data to VB net platform.


    Coderv9


    • Edited by Coderv9 Saturday, June 1, 2019 6:24 AM
    Saturday, June 1, 2019 6:23 AM
  • I take it that you do not have the source code to the original VB6 program. Otherwise your variable names would be more meaningful than VAR1. 

    Have you tried any of these links? http://www.program-transformation.org/Transform/VisualBasicDecompilers

    There does not appear to be anything in your data file that defines the record layout. 

    Here is the Pizza Margherita record. The 1,2,3,4,1 sequence would appear to be integers and correspond to the K, N, G, B, Kate  fields in your image.

    The best idea that I have is for you to use your test record. Change each field one by one and see what data changes in the file. That way you can figure out the real record layout and write an extract program to load the data into an XML format or put it into a database. 

    • Edited by MotoX80 Saturday, June 1, 2019 1:11 PM
    Saturday, June 1, 2019 11:55 AM
  • HI Dave,

    We are looking for a solution in VB.net.

    Then I'd ask for help over here.

    https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?forum=vbgeneral

     

     



    Regards, Dave Patrick ....
    Microsoft Certified Professional
    Microsoft MVP [Windows Server] Datacenter Management

    Disclaimer: This posting is provided "AS IS" with no warranties or guarantees, and confers no rights.

    Saturday, June 1, 2019 12:13 PM
    Moderator
  • Hi MotoX80,

    Finally found a solution from Old VB6 Forum :) Thank you for the time and help on this 

    http://www.vbforums.com/showthread.php?875221-Read-Dat-file-to-a-table-list-in-List-Box


    Coderv9

    Saturday, June 1, 2019 5:46 PM