Visual Basic

Re: Window is slow to instantiate - only on some machines

3-Apr-09 14:51

Hi,

look at Task Manager Performance for the CPU load while the app is starting.
If it is around 100% all the time, your app is wasting CPU cycles for some reason (do you have busy loops? polling loops?); if it is around 50% all the time, your app is busy and might be faster with more multi-threading (assuming you have a multi-core CPU); if it is rather close to zero for some time, you are waiting for something (are you accessing stuff on servers? on Internet?).

dBrong wrote:
the problem lies in the creation of the window.

Then add more observation points until you got to the specific line that causes the delay.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

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dBrong3-Apr-09 15:15

dBrong

3-Apr-09 15:15

Is there a way to preload the Pegasus Dll's?

Some users have delays of 11-20 seconds in the mybase.new method.

Re: Window is slow to instantiate - only on some machines

Luc Pattyn3-Apr-09 15:49

Hex and Ascii issue converting back and forth from text and ascii

3-Apr-09 15:49

I'm not familiar with Pegasus, so I can't tell; you might contact the vendor about it.
Is there some license scheme, possibly contacting them in real-time over the Internet?

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Cory Kimble3-Apr-09 4:37

Re: Hex and Ascii issue converting back and forth from text and ascii

3-Apr-09 4:37

I need help converting between hex, ascii and back.

I want to type in an alpha numeric like "ABC123" and save as a HEX formatted like this "## ## ## ## ## ## ## ## ## ## ## ##"

Then later read that stored value and return to the text of "ABC123"

I am having trouble reading it and returning to text.

Here is what I try.

value = value.Replace(" ", "")

        While (zero)
            shorthex = value.Substring(0, 2)
            If shorthex = "00" Then
                value = value.Substring(2, value.Length - 2)


            Else
                zero = False
            End If
            i = i + 1
        End While
        Dim b((value.Length / 2) - 1) As Byte
        Dim x As Integer = b.Length - 1
        For i = value.Length - 2 To 0 Step -2
            b(x) = value.Substring(i, 2)
            x = x - 1
        Next

        value = Long.Parse(value, Globalization.NumberStyles.HexNumber)

        Dim test As String = System.Text.Encoding.ASCII.GetString(b)

When this is done test does not show the valid Text.

Any suggestions?

I can't think of anything cool and nerdy to say.

Luc Pattyn3-Apr-09 5:05

Re: Hex and Ascii issue converting back and forth from text and ascii

3-Apr-09 5:05

Hi Cory,

your question is not really clear to me. How would you turn a six-char string ABC123 into a 24-char string (ignoring spaces)?? Please provide a full example, and/or provide the code that does the expansion.

Anyway, here are some comments on the code shown:

1.
the code is not safe, what if value starts of with all zeroes in it?

2.
Long.Parse is returning a Long, you shouldn't assign the result to value since that is a string.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Cory Kimble3-Apr-09 5:55

Re: Hex and Ascii issue converting back and forth from text and ascii

3-Apr-09 5:55

I want to get string from textbox and write to RFID device formatted in HEX "## ## ## ## ## ## ## ## ## ## ## ##"

so, my goal is to (i think) convert text into Ascii then into hex and then I can save into the format.

Then I want to read from RFID and convert back to the Text. So I think I take formatted hex and convert to hex number and then to ascii number then to Text.

I am getting screwed up on the steps.

I think this will do the Write.

Dim i As Integer
     Dim x As Integer
     'Create array
     Dim bytearray(23) As String
     For i = 0 To bytearray.Length - 1
         bytearray(i) = "0"
     Next
    
     Dim hex As String
     Dim text As String = ""
     'Change Text into ASCII
     hex = Strings.Asc(TextBox1.Text)
     'Change Ascii into HEx
     hex = Long.Parse(hex, Globalization.NumberStyles.HexNumber)
     x = 0
     'Put hex into Format
     For i = hex.Length - 1 To 0 Step -1
     bytearray((bytearray.Length - 1) - x) = hex.Substring(i, 1)
     x += 1
     Next
     'Create full formatted string to write to RFID
     If TextBox1.Text<> "" Then
     For i = 0 To bytearray.Length - 1 Step 2
     text = text + bytearray(i) + bytearray(i + 1) + " "
     Next
     text = text.Substring(0, text.Length - 1)

If "f" is typed in text box then text variable should say "00 00 00 00 00 00 00 00 00 00 02 58"

I need help converting that back to "f"

I can get it back down to 258 which I think is the hex. I need to know how to convert back to Ascii and then Text.

Any ideas?

Text

I can't think of anything cool and nerdy to say.

Luc Pattyn3-Apr-09 6:48

Re: Hex and Ascii issue converting back and forth from text and ascii

3-Apr-09 6:48

Hi,

AFAIK this is completely wrong.

1. it does not work at all for more than one character since Strings.Asc(string) only looks at the first character of the string.

2. the conversion for a single character does not work (well, it does convert, but in a nonsensical way)
The simple example where original text is "f", it is an ASCII character with numeric value 102 in decimal, which is 66 in hex.
Indeed the outcome of Strings.Asc(TextBox1.Text) is the number 102

ERROR1: you erroneously store that in the string variable named "hex" which now holds "102"

ERROR2: then you parse, i.e. decode, it as if it were a hex number, hence the result is the number 258 since 1*256+0*16+2*1 equals 258.

ERROR3: you again erroneously store that in the string variable named "hex" which now holds "258"
and finally you do a lot of moving around to get some zeroes and spaces

What you probably want is something along these lines:

Sub rfid2()
    Dim maxChars As Integer = 12
    Dim Text As String = "ABC123   f"
    Console.WriteLine("Encoding """ & Text & """ in " & maxChars & " hex chars")

    Dim length As Integer = Text.Length
    Dim result As String = ""
    Dim i As Integer

    For i = 1 To maxChars - length
        result = "00 " & result
    Next

    For i = 0 To length - 1
        Dim chr As Integer = Strings.Asc(text.Substring(i, 1))
        result = result & chr.ToString("X2") & " "
    Next
    Console.WriteLine("result=" + result)
End Sub

This generates "00 00 41 42 43 31 32 33 20 20 20 66 " where each of the characters is clearly visible in hex.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Cory Kimble3-Apr-09 9:33

Re: Hex and Ascii issue converting back and forth from text and ascii

3-Apr-09 9:33

Ok, that works, but how do I take the ASCII and display the text?

I can't think of anything cool and nerdy to say.

Luc Pattyn3-Apr-09 10:05

Re: Hex and Ascii issue converting back and forth from text and ascii

3-Apr-09 10:05

Hi,

To reverse the process, you need to perform the reverse of the same steps, in reverse order.
AFAIK the reverse of Strings.Asc is Strings.Chr, and the reverse of int16.ToString("X2") is int16.Parse() where you will want the right NumberStyle. I leave the details for you to work out.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Cory Kimble3-Apr-09 10:55

SaveFileDialog with Serialport

3-Apr-09 10:55

Got it! Thank you.

I can't think of anything cool and nerdy to say.

Quin Nee3-Apr-09 1:39

Quin Nee

3-Apr-09 1:39

I would like to save the data logs from the serialport received events into a filename. The problem is, I am running a series of test using the queue collection and I want to save each test in a different filename, (e.g Test 1, Test 2, Test 3, etc). Is it possible to use savefiledialog with it? Or is there some other ways to get around to doing this?

Re: SaveFileDialog with Serialport

Luc Pattyn3-Apr-09 3:27

problem in overwriting the previous setup

3-Apr-09 3:27

Hi,

the SerialPort.DataReceived event runs on a separate thread since it is asynchronous to anything you are doing; as such you are not allowed to touch any Control (including Forms, dialogs, and SaveFileDialog object) unless you use the proper InvokeRequired/Invoke method.

Also it does not seem like a good idea to interact with the user from within the DataReceived event, since more data will be arriving while you are waiting for the user's reaction.

Furthermore, the SaveFileDialog is *not* for saving data to a file, it is intended for letting the user *choose* a filename. When you need several file names, you probably want an algorithm to generate a series of filenames (say test###.log where ### is a sequence number)

What you should do is collect the data as it comes in, using whatever means appropriate (maybe a List<string> or a List<byte[]> depending on whether you accept text or arbitrary bytes); and in a different part of your app process or save the data, and interact with the user if and when necessary.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Pankaj Garg3-Apr-09 0:47

Pankaj Garg

3-Apr-09 0:47

Hi,

My Front end is VB.net 2008
I was trying to fix the problem of overwriting the previous setup problem. So while surfing the net, i got the following link useful.

http://social.msdn.microsoft.com/Forums/en-US/winformssetup/thread/aea77734-3517-4301-8525-a40748a7905c/[^]

But I have a query, there I found the following code.

If My.Settings.UpdateRequired Then
            My.Settings.Upgrade()
            My.Settings.UpdateRequired = False
            My.Settings.Save()
        End If

Can you tell me, In which file I should write this code?

Re: problem in overwriting the previous setup

Tom Deketelaere3-Apr-09 1:47

Tom Deketelaere

3-Apr-09 1:47

Before any off your settings are called so best bet is the application startup event.

Can only delete numbers in access database

hendrikbez2-Apr-09 22:05

hendrikbez

2-Apr-09 22:05

I can only now delete numbers from acces 2003 and not text. I have tryd this diffrent code, and all of them only delete numbers Eg "888".

It cant delete "myname" or "1 myname" only if everthing is numbers

MyOledbCommand.CommandText = "DELETE * FROM tblokkies WHERE leidraad='" & ListBox1.Items(ListBox1.SelectedIndex) & "'"

MyOledbCommand.CommandText = "DELETE * FROM tblokkies WHERE leidraad = """ & ListBox1.Items(ListBox1.SelectedIndex) & """"

MyOledbCommand.CommandText = "DELETE * FROM tblokkies WHERE leidraad='" & ListBox1.Items(ListBox1.SelectedIndex).ToString() & "'"

My colums is only set to text and leidraad is the primary key.
I don't know if it has to do with my insert to the table, here is the code I am using.

MyOledbCommand.CommandText = "Insert Into Tblokkies " & "(leidraad,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10,A11,A12) " _
            & "Values (" _
            & "'" & String1 & "', " _
            & "'" & String2 & "', " _
            & "'" & String3 & "', " _
            & "'" & String4 & "', " _
            & "'" & String5 & "', " _
            & "'" & string6 & "', " _
            & "'" & string7 & "', " _
            & "'" & string8 & "', " _
            & "'" & string9 & "', " _
            & "'" & string10 & "', " _
            & "'" & string11 & "', " _
            & "'" & string12 & "', " _
            & "'" & string13 & "')"

Jay Royall2-Apr-09 22:20

Jay Royall

2-Apr-09 22:20

What are you populating ListBox1 with? A collection of objects or are they just strings?

hendrikbez2-Apr-09 22:29

hendrikbez

2-Apr-09 22:29

I am usinf this to fill my listbox1

Do While MyDataReader.Read

           ListBox1.Items.Add(MyDataReader("Leidraad"))

           Dim MyItem = ListView1.Items.Add(MyDataReader("Leidraad".ToString))

           With MyItem

               .SubItems.Add(MyDataReader("A1").ToString)
               .SubItems.Add(MyDataReader("A2").ToString)
               .SubItems.Add(MyDataReader("A3").ToString)
               .SubItems.Add(MyDataReader("A4").ToString)
               .SubItems.Add(MyDataReader("A5").ToString)
               .SubItems.Add(MyDataReader("A6").ToString)
               .SubItems.Add(MyDataReader("A7").ToString)
               .SubItems.Add(MyDataReader("A8").ToString)
               .SubItems.Add(MyDataReader("A9").ToString)
               .SubItems.Add(MyDataReader("A10").ToString)
               .SubItems.Add(MyDataReader("A11").ToString)
               .SubItems.Add(MyDataReader("A12").ToString)

           End With

       Loop

and these also

Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged

       Dim SqlStr As String


       SqlStr = "Select * FROM tblokkies WHERE leidraad='" & ListBox1.Items(ListBox1.SelectedIndex).ToString() & "'"

       'SqlStr = "Select * from tblokkies where leidraad = """ & ListBox1.Items(ListBox1.SelectedIndex) & """"

       FillTextBox(SqlStr)
   End Sub

Jay Royall2-Apr-09 22:47

Jay Royall

2-Apr-09 22:47

OK. Well it all looks fine to me. What I would do is set a breakpoint just before your delete statement and check the value of ListBox1.Items(ListBox1.SelectedIndex) to make sure that you're getting the correct value. Sorry I can't be of more help.

JC.KaNNaN3-Apr-09 20:57

JC.KaNNaN

3-Apr-09 20:57

you can try below below one

MyOledbCommand.CommandText = "DELETE * FROM tblokkies
WHERE leidraad=" & ListBox1.Items(ListBox1.SelectedIndex).ToString() & ""