VB6 to VBNET Structure Problem

[tcomputerchip]

Ok this one may be difficault for some of you.


This is the problem. I have a converter program that converts binary data to text formated data. The class was written in VB6. I would like to convert the class to VBNET.

The problem is I dont know anything about Structures except that it replaces Type declerations.

Now, when I convert the Type over to structure I have many errors still in my dimentioned varialbles.

Example: VB6

Type bLineData
    ByteOfData      As String * 1       1 Char only
    LotsOfData(25)      As Byte         25 bytes only
End Type

Change to VBNET:

Structure bLineData
    Dim ByteOfData      As String * 1       Not Working 
    Dim LotsOfData(25)    as Byte           Not Working
End Structure

If someone could modify the code below, or parts of it and give me example of how I should convert the code to VBNET that would be great.

Code Working On:

Module modConvert

Type LabelArea
    DateTimeValue(5) As Byte
    FileName            As String * 8    Redundent but here
    DeviceName          As String * 10   Name of part or part number
    Operator            As String * 10   Person that ran/collected test data
    TestingMode As Byte                  first bit 0 = TBB, 1 = TBS
    StationName         As String * 1    Station A,B,C,D and F
    LotName             As String * 10   Lot for device that were tested
    Comment             As String * 50   Comments of test
    TimePoint As Integer                 Test number mostly for HiRel applications\
    SetQuantity As Integer               Number of device that were tested
    LoggingRate As Integer               Results sorted after N test 1 in 5, 2 in 10
    TestMax As Integer                   Number of test used to collect data
    DataBlockNum As Integer              Not used currently
    LoggedQuantity As Integer            Actual Logged quantity
    IndexMax As Integer                  Device Index
    Reserved(17) As Byte                 Future use
End Type

Type TestItemArea
    TestNumber          As Byte         Test Number
    ItemGroupCode       As Byte         Item Group Code
    ItemCode            As Integer      Item Code
    BEConditionFlag     As Byte         BE Condition & Flag
    ResultBiasFlag      As Byte         Result as BIAS Flag
    LimitItemName       As String * 6   Limit Item Name
    LimitUnit           As Integer      Limit Unit, second byte not used
    LimitValue          As Single       Limit Value
    LimitMax            As Single       Limit Min
    LimitMin            As Single       Limit Max
    bias1Name           As String * 4   Bias 1 Name
    bias1Unit           As String * 2   Bias 1 Unit
    bias1Value          As Single       Bias 1 Value
    bias2Name           As String * 4   Bias 2 Name
    bias2Unit           As String * 2   Bias 2 Unit
    bias2Value          As Single       Bias 2 Value
    TimeCondition       As String * 4   Time Condition Name
    TimeUnit(1)         As Byte         Time Unit
    TimeValue           As Single       Time Value
    DLIFlags            As Byte         DL Inhibit Flags
    Reserved(6)         As Byte         Reserved
End Type

Type WafferData
    wafferID         As Byte            Always W
    wafferNumber     As Byte            Waffer Number
    NumberOfDevices  As Integer         Number of devices
    Reserved         As Integer         Reserved
End Type

Type DeviceData
    deviceID         As Byte            Always D
    ZeroZero         As Byte            Always 00
    SerialNumber     As Integer         Number of devices
    BinNumber        As Integer         Reserved
End Type

Type TestData
    TestNumber      As Byte             TestNumber
    Flags           As Byte             Flags
    TestValue       As Single           Test Resualt Value
End Type

Type bLineData
    ByteOfData      As String * 1       Extract data for check
End Type






End Module

 

[Bucky]

All arrays dimensioned in VB.NET begin their indexes at zero, so
Dim LotsOfData(25) As Byte actually declares an array with a
length of 26.

Fixed-length strings are not supported in VB.NET, as youve
noticed. One way I could think of recreating this effect is an
array of Char variables, so LimitItemName As String * 6 would
change to LimitItemName(5) As Char, although I dont think its
very efficient to convert between a Char array and a string when
youre changing the value of this variable. There may be another
way around this. If you stuck all these variables in a class, you
could trim the string in the Property accessor subs to ensure its
size does not exceed the maximum you want.

Its also worth noting that an Integer in VB6 is 16-bit, but an
Integer in VB.NET is 32-bit. In VB.NET, the 16-bit number variable
is Short. Bytes remain the same old 8 bits.

For more info, read the article "Upgrade Recommendation: Avoid
Arrays and Fixed-Length Strings in User-Defined Types" in the
help files.

 

[tcomputerchip]

Thanks for the reply. I know about the Integer problem, I have delt with that with several of the classes I have worked on.

The "LotsOfData(25) As Byte" does not work at all.

 

[tcomputerchip]

Ok, this is starting to get very frustrating. VB.NET is not VB6 at all. If you someone tells you different kick them in the shins!

This is the problem:

I need to read binary data from a file. In VB6 this is what it looked like:

        Dim getLabelArea As LabelArea This is my Structure Code in VB6

Open file code for binary omitted
            Get(FileInNum, getLabelArea, FileIndex)
            This would take the Type and store the values read in binary mode into the Type Structure

This is VBNET
[VB]

Seek(FileInNum, FileIndex)
Input(FileInNum, getLabelArea) I need for getLabelArea to extract the data in the dimentioned order and store the data in the Difined Structure.
[/VB]

There maybe another way to read the data binary other than using the FileGet function. If there is where can I get some information or code on this?

 

[Divil]

Why not try serialization of classes? You can do that with XML or binary methods, to name two. The days of opening files, loading and parsing are gone, and so are the ones of relying on structures with fixed-length members, let the framework do the work for you.

I suggest XML Serialization as a great way to persist classes. Its saved me a boatload of work.

 

[tcomputerchip]

There is not too much documentation on the XML serialization. I only found 1 document that shows a sample. And it does not look like what I am trying to do.

If you could explain, or give sample code of this XML method, please do so.

 

[brian728s]

I cant get fixed length arrays to work either, but you can get a fixed length string with this:

<vbfixedstring(x)> public StringName as string

where x is the number of letters

UPDATE:

Try using <vbfixedarray(x)> public ArrayName as whatever.

 

[tcomputerchip]

Update:

I have had no problem with the Top structure. The <VBFixedArray(6)> I knew about and was using.

To help in your troubleshooting, the section of the file that I am reading and having problems with is the LimitItemName; its stored as ASCII and is 6 chars long.

My problem is on the second Stucture when calling it through the file reader:

Module:
    Public Structure LabelArea
        Public DateYearTested As Byte
        Public DateMonthTested As Byte
        Public DateDayTested As Byte
        Public DateHourTested As Byte
        Public DateMinuteTested As Byte
        Public DateSecondTested As Byte
        <VBFixedString(8)> Public FileName As String             Redundent but here (8)
        <VBFixedString(10)> Public DeviceName As String          Name of part or part number (10)
        <VBFixedString(10)> Public Operator As String            Person that ran/collected test data (10)
        Public TestingMode As Byte                               first bit 0 = TBB, 1 = TBS (1)
        Public StationName As Char                               Station A,B,C,D and F (1)
        <VBFixedString(10)> Public LotName As String             Lot for device that were tested (10)
        <VBFixedString(50)> Public Comment As String             Comments of test (50)           
        Public TimePoint As Short  Test number mostly for HiRel applications\
        Public SetQuantity As Short                             Number of device that were tested
        Public LoggingRate As Short                             Results sorted after N test 1 in 5, 2 in 10
        Public TestMax As Short                                 Number of test used to collect data
        Public DataBlockNum As Short                           Not used currently
        Public LoggedQuantity As Short                          Actual Logged quantity
        Public IndexMax As Short                               Device Index
        <VBFixedArray(18)> Public Reserved As Byte               Future use (18)
    End Structure

    Public Structure TestItemArea
        Public TestNumber As Byte                               Test Number
        Public ItemGroupCode As Byte                            Item Group Code
        <VBFixedArray(2)> Public ItemCode As Byte                                Item Code
        Public BEConditionFlag As Byte                          BE Condition & Flag
        Public ResultBiasFlag As Byte                           Result as BIAS Flag
        <VBFixedString(6)> Public LimitItemName As String       Limit Item Name
        Public LimitUnit As Short                               Limit Unit, second byte not used
        Public LimitValue As Single                             Limit Value
        Public LimitMax As Single                               Limit Min
        Public LimitMin As Single                               Limit Max
        <VBFixedString(4)> Public bias1Name As String           Bias 1 Name
        <VBFixedString(2)> Public bias1Unit As String           Bias 1 Unit
        Public bias1Value As Single                             Bias 1 Value
        <VBFixedString(4)> Public bias2Name As String            Bias 2 Name
        <VBFixedString(2)> Public bias2Unit As String            Bias 2 Unit
        Public bias2Value As Single                             Bias 2 Value
        <VBFixedString(4)> Public TimeCondition As String       Time Condition Name (4)
        <VBFixedString(2)> Public TimeUnit As Byte               Time Unit (2)
        Public TimeValue As Single                              Time Value
        Public DLIFlags As Byte                                 DL Inhibit Flags
        <VBFixedArray(7)> Public Reserved As Byte               Reserved
    End Structure

This is a stripped down version of what I am doing, the section of code that I am having problems with is noteded below.

Function ConvertFile() As Boolean

...Inside class function

                FileIndex = 1
                FileGet(FileNum, getLabelArea, FileIndex) , FileIndex)
                FileIndex = FileIndex + 127

...Removed Company code...

...Continue Public code...

                    For i = 1 To getLabelArea.TestMax
                        FileGet(FileNum, getTestItemArea, FileIndex)


                        TestItemL1 = TestItemArea.LimitItemName.ToString  Always returns 0, not wanted, should return String of Text (6 chrs long)
                        FileIndex = (i * 64) + 128
                    Next i
...End Public code...
End Function

 

[IpSteal]

Hi, I am having problems with using VBFixedArrays.

I am declaring it like so:

<VBFixedArray(MaxSize)> Dim myArray() as String

but when I go to initialize all the indices like so:

For i=0 to MaxSize-1
Template.myArray(i) = ""
Next i

I get an error "Object reference not set to an instance of an object"

My template is set up as follows:

<code>

Structure TemplateType
...
<VBFixedArray(MaxSize)> Dim myArray() as String
...
Public Sub Initialize()
ReDim myArray(MaxSize)
End Sub
End Structure

Public Template As TemplateType

Public Function InitializeTemplate() as Object
...
For i = 0 to MaxSize-1
Template.myArray(i) = ""
The line above fails
Next i
...
End Function

</code>

Please help as I have sadly been trying to figure this out for a good 10+ hours.

Thank you
ip

 

[IpSteal]

Forget it, problem solved.

This was originally a vb6 that i upgraded to .net and it created a initialize function that redimd myArray, but the initialize function was never actually called, so i just through a call to it in my initialize template function before i started setting myarray(i) equal to anything.

Arg, the relief of finding such a simple solution after ragging my brains out for 10+ hours.