Visual Basic

John Kuhn25-Feb-04 14:07

John Kuhn

25-Feb-04 14:07

One of two things you could do:

1) Create a Class:
Assuming VB.NET: You will create a new class library named Player.vb.
Assuming VB6: You will create a new class library named Player.cls.

2) Create a type/structure:
Assuming VB.NET: Create a structure definition using Structure...End Structure.
Assuming VB6: Create a type using Type ... End Type

What a piece of work is man, how noble in reason, how infinite in faculties, in form and moving how express and admirable . . . and yet to me, what is this quintessence of dust? -- Hamlet, Act II, Scene ii.

Codemonkey8510-Mar-04 12:14

Codemonkey85

10-Mar-04 12:14

Well, I went ahead and made a new class library (my new variable type ends up being Munchkin.Player.Character). I can do things now like assign "Male" to Character.Gender, but I can also do wacky things like Character.Gender = "Chicken". Another thing is that the maximum level is supposed to be ten, but I could make Character.Level whatever integer I want, even negatives. What do I do to limit what kinds of genders there are, or specify which ones do and don't work?

As I sit here, I contemplate the last words of Socrates: "I drank what?".

John Kuhn10-Mar-04 13:44

John Kuhn

10-Mar-04 13:44

Well, you could do a couple of things. You could have an Enum in your project, like:

Namespace Munchkin
    Public Enum Genders
        Male
        Female
    End Enum
End Namespace

Then, you could declare your Gender field like:

Public Gender As Genders

And the only valid thing to put in it would be:

someCharacter.Gender = Genders.Male

You could do the same thing with levels, or you could throw an exception if a character's level is set below 1 or above 10:

Public Class Character
    Private _level As Integer
    Public Property Level() As Integer
        Get
            Return _level
        End Get
        Set(ByVal Value As Integer)
            If Value < 1 Or Value > 10 Then
                Throw New ApplicationException("Level must be between 1 and 10")
            Else
                _level = Value
            End If
        End Set
    End Property
End Class

But guess what? Your Character is starting to sound more like a class than a structure...

What a piece of work is man, how noble in reason, how infinite in faculties, in form and moving how express and admirable . . . and yet to me, what is this quintessence of dust? -- Hamlet, Act II, Scene ii.

Codemonkey8511-Mar-04 4:58

Codemonkey85

11-Mar-04 4:58

>But guess what? Your Character is starting to sound more like a class than a structure...

In that case, I must have misinterpreted your orginal advice; I had a project named Munchkin, a Class named Player, and a Structure named Character. It looked something like this:

Structure Character<br />
        Public Name As String<br />
        Public Gender As String<br />
        Public Level As Integer<br />
    End Structure

But I guess I should do the Class thing and the Structure thing seperately. Anyway, thanks for the help. I'm gonna try the Enum and Exception code now.

As I sit here, I contemplate the last words of Socrates: "I drank what?".

VB Script Password InputBox

John Kuhn12-Mar-04 2:51

John Kuhn

12-Mar-04 2:51

Although, on the other hand, you could produce a Class that acts like a Character factory. Anyway, glad I could lend a hand.

What a piece of work is man, how noble in reason, how infinite in faculties, in form and moving how express and admirable . . . and yet to me, what is this quintessence of dust? -- Hamlet, Act II, Scene ii.

morde1ac25-Feb-04 9:47

morde1ac

25-Feb-04 9:47

I am working on some VB Script and am using an InputBox that accepts a password. When the user types in the password, I would like it to show up as *********
Any help doing this would be great. Here is some of the code:

strUserIn = InputBox("Enter Password")
if strUserIn <> "" then
Set fs = CreateObject("Scripting.FileSystemObject")
strFileName = fs.BuildPath(Wscript.ScriptFullName & "\..", "~userp.txt")
strFileName = fs.GetAbsolutePathName(strFileName)
Set ts = fs.OpenTextFile(strFileName, 2, True)
ts.WriteLine strUserIn
ts.Close
end if

Re: VB Script Password InputBox

Dave Kreskowiak25-Feb-04 13:00

25-Feb-04 13:00

VBScript and the Windows Script Host don't yet support a password-type input box yet. You'll have to use an external component of some kind to do this or make your code run in an HTML page and use an HTML password box. But, there are limitation on what your script can do inside a browser.

RageInTheMachine9532

Driving a motor

Looping_Eagle25-Feb-04 6:56

Looping_Eagle

25-Feb-04 6:56

High timer experts, OMG | :OMG:

I have a problem very similar to the "Help clock generate" thread.
I want to control a stepper motor of an electrophoresis unit.
The Motor should be driven with (only) 250 hz.
The low precicion timers using the message que (windows.froms.timers)
are not usefull for this purpose (Instantly I wandered why the motor
does not perform all steps with the timer set to 50 Hz, but meassuring the
intervals using the system performancecounter revealed, that about every
10th interval is only 203 ticks long -- for what ever reason)

Looking for a solution, I came accross -Queue timers- which should be able to
deal with this problem. Unfortunately, I am not familiar with C programming language
and all the examples were written in C (e.g. here).

Is there a possibility to run such a timer from VB.net?

Thanks in advance

Armin

Re: Driving a motor

Dave Kreskowiak25-Feb-04 8:51

25-Feb-04 8:51

If my math is right, at 250Hz, you need to fire the event every 4 milliseconds. The timers that your finding all have 1 millisecond resolution. At that low an interval, the millisecond timers are not really that accurate. They can be off by as much as a millisecond when your app receives the notification.

I think that part of the problem is the priority that your process is running under. You might want to consider running your app and then, before you start the timer test, go into the Task Manager, click on the Processes tab, right-click on your app and bump the priority up to High or RealTime to see if the interval stabilizes for you.

RageInTheMachine9532

CRC32

johnjsm25-Feb-04 5:24

25-Feb-04 5:24

Hi All
I have started writing a program to get the crc32 of a file. I have this working fairly well. The only thing now is I need to get the crc32 of a complete folder and its contents and get an overall checksum for it, but I don't seem to be able to get it to work. If anyone can give some insight to this problem it would be great. Also I cannot get to display the file size of the file i am checking.
Thanks

Dave Kreskowiak25-Feb-04 7:13

25-Feb-04 7:13

You might want to show the code your using to get a CRC on a directory and its contents.
Are you looking to get the CRC on all the filenames? Or are you trying to get a combined CRC of all the files in the directory?

RageInTheMachine9532

johnjsm25-Feb-04 22:17

25-Feb-04 22:17

I am trying to get a combined CRC for all the files. I am using the FastCRC library to try get the code to work. So far I can get the crc of a single file I have tried to code it to check the directory but it never works so I usually start from scratch again.

Dave Kreskowiak26-Feb-04 1:24

26-Feb-04 1:24

Code samples are important so we can see what your doing!

Your going to have to get the CRC of each file, one at a time. I downloaded the FastCRC library and according to the docs your can use FCRC32_CalculateFile to get the CRC of each file. This is a little pseudocode to illustrate:

' Assuming VB.NET
Dim checksum as Integer
 
FCRC32_Init()
 
For Each Filename in Directory
    FCRC32_CalculateFile( checksum, Filename )
Next
 
MsgBox( FCRC32_LongToHex32( checksum, True ) )

RageInTheMachine9532

johnjsm26-Feb-04 5:24

26-Feb-04 5:24

This is the main code that I was using

Private Sub cmdCRC32_click()
Dim checksum As Long
Dim buffer As Long
If txtFileInfo.Text = "" Then
MsgBox "PLEASE SELECT A FILE", vbExclamation, "No File Selected"
End If

'Calculate the CRC32 checksum and MD5 of a file
If FCRC32_CalculateFile(checksum, txtFileInfo.Text) = 0 Then
txtInfo.Text = txtFileInfo.Text & vbCrLf & _
"CRC32= " & FCRC_LongToHex32(checksum, True) & vbCrLf & _
"MD5=" & QHASH_FileHexDigest(MD5_ALGID, txtFileInfo.Text, True)
End If

End Sub

Thanks

Dave Kreskowiak26-Feb-04 8:27

26-Feb-04 8:27

So far, it looks good, though you can drop the declaration for 'buffer'. You'll never use it...

Now all you need to is to wrap this in code that goes thru a list of filenames and your all set. You can use the Dir() function to do this:

' Assuming VB.NET
' For VB6, change Integer type to Long
Dim iCheckSum As Integer
Dim strFilename As String
 
    FCRC32_Init()
    strFilename = Dir( startingPathAsString )
    Do While strFilename <> ""
        FCRC32_CalculateFile( iCheckSum, Filename )
        strFilename = Dir()
    Loop
 
    MsgBox( "CRC32: " & FCRC32_LongToHex32( iCheckSum, True ) )

RageInTheMachine9532

johnjsm4-Mar-04 4:28

4-Mar-04 4:28

I'm still having huge problems using the dir function. Is there a sample of code i could get

Dave Kreskowiak4-Mar-04 5:45

4-Mar-04 5:45

You'll have to post what you have so we can see what your doing. The only code example I have is in my previous post.

RageInTheMachine9532

r i s h a b h s26-Feb-04 19:07

r i s h a b h s

26-Feb-04 19:07

can u plz. tell me wots CRC32

rIsHaBh

Dave Kreskowiak27-Feb-04 4:13

27-Feb-04 4:13

It's a 32 bit Cyclic Redundancy Check. Its used to give a block of data a value that represent an error check. The block of data is transmitted with it's CRC value, then the receiver gets the block, performs a CRC calculation on it and compares that value with the CRC that was transmitted with the block of data. If the two don't match, there was problem with the transmission.

RageInTheMachine9532

johnjsm29-Feb-04 1:52

29-Feb-04 1:52

CRC stands for Cyclic Redundency Check. Where I work we use it to check .iso files transfered over the network to make sure that it is the same. If anything happened to it in transfer there would be a difference. So if the CRC32 is the same then the file is the same. It can be used to check all the files on a cd also, so if any file changed in creating a cd the CRC32 checksum would be different than that of the master disc.