vbCity - The .NET Developer Community: Unanswered Threads

status of queue printer job vb 6.0

sal21 sal21 — Wed, 05 Feb 2025 11:46:30 GMT

How to check the status of queue printer job vb 6.0?

Global 2D string array not visible throughout program

vbFossil — Sat, 07 Sep 2024 17:41:51 GMT

Hello! I am converting an old VB6 program to VB.Net and there are subtle differences that I am not aware of. In VB6, I could define 2D string arrays at the program header (before procedural coding began) and those variables were visible from everywhere. That does not work in VB.Net.

When I run the program I get this error "Object reference not set to an instance of an object.". The program is aware that the variables exist, but it seems as if they are not initialized.

Here is a snippet of the code. It is not functional but merely displayed to show the location of the variables and where they are called from.

Public Class Form1

Public strNewTools(200, 3) As String

Public strOldTools(200, 3) As String

Public strOldSort(200, 3) As String

Public Sub cmdCompare_MouseDown(sender As Object, e As MouseEventArgs) Handles cmdCompare.MouseDown

intInner = intInner + 1

If strNewTools(intOuter, 3) = strOldTools(intInner, 3) Then

strToolTmp = strToolTmp & strNewTools(intOuter, 1) & strOldTools(intInner, 1) & vbCrLf

strNewSort(intOuter, 1) = strNewTools(intOuter, 1)

strNewSort(intOuter, 2) = strNewTools(intOuter, 2)

strNewSort(intOuter, 3) = strNewTools(intOuter, 3)

strOldSort(intOuter, 1) = strOldTools(intInner, 1)

strOldSort(intOuter, 2) = strOldTools(intInner, 2)

strOldSort(intOuter, 3) = strOldTools(intInner, 3)

End If

End Sub

End Class

I even tried to make the definition "Public" as well as the referenced subroutine. No luck.

What is the right way to do this?

Thank you, Steveb

Upgrade, but will it work?

davek0974 — Mon, 05 Jun 2017 11:50:45 GMT

Looking to upgrade our system but have a couple of questions...

Currently our SQL database is SQL7(2003 vintage) and the new one will be SQL 2016, does anyone know if you can still talk to SQL 2016 using OLEDB/ADO connections as my app uses that method??

Next, we all know VB was killed off some time ago, its the only language i know, what would be the replacement for it for modern-day programming of office/accounts/database programming of front-end apps? I dont think i will have the courage to start re-writing this massive app but I woul dbe interested to see what visual programming stuff is out there.

Thanks

VB6 AFTER MS WINDOWS 10

elico — Sun, 01 Nov 2015 11:24:18 GMT

Is it ttrue that VB6 will not be suppotred in the OS that will come after AINDOWS 10 ?

Elico

real time counter of popolation in Italy

sal21 sal21 — Sat, 25 May 2024 17:07:58 GMT

How to insert a real time counter of population of Italy, in a label or text box?

Read PDF File using VB.NET

Lalit Acharekar — Sun, 24 Mar 2024 03:18:34 GMT

I am having Scanned PDF File /having headers like Date,PO. No, Item Description, etc I want to read the Values written In front of/below these

Titles.I used the below code but it isnt working and giving me the desired result

Please assist

Imports Emgu.CV
Imports Emgu.Util
Imports Emgu.CV.OCR
Imports Emgu.CV.Structure
	Dim OCRz As Tesseract = New Tesseract("tessdata", "eng", Tesseract.OcrEngineMode.OEM_DEFAULT)
    Dim pic As Bitmap = New Bitmap(270, 100)
    Dim gfx As Graphics = Graphics.FromImage(pic)

gfx.CopyFromScreen(New Point(Me.Location.X + PictureBox1.Location.X + 4, Me.Location.Y + PictureBox1.Location.Y + 30), New Point(0, 0), pic.Size)
        PictureBox1.Image = pic
        PictureBox1.Image = Nothing

 OCRz.Recognize(New Image(Of Bgr, Byte)(pic))
        RichTextBox1.Text = OCRz.GetText

Saving a Textbox List to a Database table

Stephen Mills — Sat, 18 Mar 2023 23:11:27 GMT

Hi,

The code below is used to save a list thats in a textbox to an Access database table.

The code sort of works, it saves the data but after its saved about 80 ish lines, it then muddles up the order of the list.

So once saved, all the items in the list are saved to the database but it is not in the correct order.

'Open connection to database tbl_PartsList
    Dim cnnSave As ADODB.Connection
    Set cnnSave = New ADODB.Connection
    cnnSave.ConnectionString = "Provider = Microsoft.Jet.OLEDB.4.0;" & "Data Source =" & frmReportPg1!lblDbasePath.Caption
    cnnSave.Open

'Delete all records from Field "Parts" so field is clear for new List to be saved
    cnnSave.Execute "delete * from tbl_partslist"


'Save new parts list from set-up page to database

    Set rsSavePartsToDBase = New ADODB.Recordset
    Dim i As Integer
    Dim sArray() As String
    
     sArray = Split(PListText.Text, vbCrLf)
     For i = 0 To UBound(sArray)
         rsSavePartsToDBase.Open "insert into tbl_partslist (parts) values ('" & sArray(i) & "')", cnnSave, adOpenKeyset, adLockPessimistic
     Next i


    Set rsSavePartsToDBase = Nothing
    Set cnnSave = Nothing

If anyone can tell me whats wrong with the code it would be much appreciated.

Thanks

SKM

Parameter error converting string to decimal...

Steve Light — Sun, 05 Feb 2023 21:57:53 GMT

I don't know what I am missing but I am getting the " Failed to convert parameter value from a string to a decimal" when I am trying to INSERT data.

I have a access database with a table that has decimal fields. I am using decimal field because I need to store a number

like xx.xx.

The field is set as:

Field size as Decimal

Precision as 4

Decimal places as 2

This is the parameter I am using. I have tried many ways I have found on internet search but none work.

.Parameters.Add(New System.Data.OleDb.OleDbParameter("@RateUnitRate1", System.Data.OleDb.OleDbType.Decimal, 4, CType(tbRateUnitRate1.Text.Trim, Decimal)))

I know the textbox has a potential decimal value because when I check it with,

Dim rate As Decimal
        If Not Decimal.TryParse(tbRateUnitRate1.Text, rate) Then
            'Textbox does not contain a decimal number - do whatever you think is appropriate
            MsgBox("Not a valid input")
            tbRateUnitRate5.Text = ""
            tbRateUnitRate5.Focus()
            Exit Sub
        End If
        rate = CType(tbRateUnitRate5.Text.Trim, Decimal)
        MsgBox(rate.ToString)

I get a value of 3.50.

What am is missing.

How to handle a blank textbox that won't let me exit the form.

Steve Light — Fri, 27 Jan 2023 21:36:40 GMT

I have a CUDA form that I use to add meter readings from customers. It contains a EXIT button, multiple text boxes. One of the text boxes is the variable that I use to find the meter information. When I when I want to exit the form and the textbox is blank and has focus then the Leave event is fired.

I have been trying to add code to stop the rest of the event from executing but I have been unsuccessful.

Please give me some advise to what I am missing.

Below is one of my attempts that doesn't work. It catches the blank text but doesn't execute the "Disposal".

Private Sub tbReadMeterNo_Leave(sender As Object, e As EventArgs) Handles tbReadMeterNo.Leave


        If tbReadMeterNo.Text = "" Then
            MsgBox("ReadMeterNo is empty")
me.Dispose
        End If

        Try
            Call connection()
        Catch ex As Exception
            MsgBox(ex.Message, MsgBoxStyle.Critical)
                errornumber = 165 'Assigned error number for logging & debugging.
                clsLogFile = New LogFile(ex.Message, errornumber)
            End Try

            Try
            Dim command = New OleDb.OleDbCommand
            Dim drMeter As OleDbDataReader = Nothing

                With cm
                    .Connection = con
                    .CommandText = "SELECT * FROM tblMeter WHERE MeterNo = @MeterFindString"
                    Try
                        .Parameters.Clear()
                        .Parameters.Add("@MeterFindString", OleDbType.Integer).Value = CInt(tbReadMeterNo.Text)
                    Catch ex As Exception
                        MsgBox(ex.Message, MsgBoxStyle.Critical)  '<----- This kicks an error "Conversion from string "" to type 'Interger' is not valid."

I know why the error happens. How do I code around it.?

A Very happy New Year 2023!

HARISH — Sat, 31 Dec 2022 07:38:46 GMT

Wishing All Vbcity community members ...

A very happy and prosperous new year 2023!

Read Binary File into ListBox Problem

Steve B — Mon, 15 Aug 2022 21:59:37 GMT

Hi, Haven't been here for years
Been trying everything to open a binary file into a listbox
and basically just getting a 0 in the box or with the code below
at the line = listBox1.Items.Add(br.ReadBytes(((int)br.BaseStream.Length)));
I will get Byte[]Array in the box, with the streamreader code below that I get
some binary code in the box, really stuck and need help.
Thanks
Steve

if (openFileDialog1.ShowDialog() == DialogResult.OK)
{

string filename = openFileDialog1.FileName;
FileStream fs = new FileStream(filename, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fs);
br.BaseStream.Position = 0;
for (int i = 0; i < br.BaseStream.Length; i++)
{
listBox1.BeginUpdate();
listBox1.Items.Clear();
listBox1.Items.Add(br.ReadBytes(((int)br.BaseStream.Length)));
listBox1.EndUpdate();

}
br.Close();
fs.Close();
///StreamReader streamReader = new StreamReader(filename);
///listBox1.Items.Clear();
/// List<string> lines = new List<string>();
/// string line;
/// while ((line = streamReader.ReadLine()) != null)
/// { listBox1.Items.Add(line); }

}
}

INSET VALUE IN COMBOBOX HTML PAGE

sal21 sal21 — Tue, 11 Jan 2022 14:30:08 GMT

based the link:

http://anagrafe.cng.it/anagrafe/geometri.aspx

how to insert value from MyVar="LIVORNO" in combobox (collegio), and click on button "cerca geometri"

tks.

Sorry but really urgent.

Update connectionString at runtime

Donald Neisler — Thu, 23 Dec 2021 22:22:42 GMT

I am attempting to update my applications connectionString and runtime, and it is giving me problems. Any assistance is greatly appreciated.

Public Sub SaveConnectionString(ByVal conString As String)
        Dim name As String = "MyDatabaseConnectionString"
        Dim config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)
        Dim section = CType(config.GetSection("connectionStrings"), ConnectionStringsSection)
        section.ConnectionStrings(name).ConnectionString = conString
        config.Save(ConfigurationSaveMode.Modified)
        ConfigurationManager.RefreshSection("connectionStrings")

 End Sub

I get a "System.NullReferenceException: 'Object reference not set to an instance of an object.'" on line 5.

Date column in a datagridview

Michael Newman — Wed, 27 Oct 2021 14:21:39 GMT

Many years ago I had a problem with a date column in a data bound datagridview. When the application was running and a new row was selected, the date column automatically displayed the system date. That is what I wanted it to do. The problem was that if you did not specifically select a date - even if it was today's date - it would not be save to the database. The cell was left blank. I did find an answer on the web but it has been lost.

The frustrating part of this is that I have had 2 computers crash on me within a few days of each other resulting in the loss of the solution to this problem. All that I can remember is that a new sub with only a few lines were used in the code to force the column to automatically select the computer's system date. No selection required by the user.

Can anyone help please? I have been searching on the web for over a day and cannot find the answer.

TreeView BackgroundImage

Tim Alvord — Fri, 08 Oct 2021 15:58:46 GMT

Hi,

I am trying to add a BackgroundImage to a TreeView. It looks like the only way this will work is to Inherit from TreeView and override OnPaintBackground(System.Windows.Forms.PaintEventArgs pevent). If I do this it works, but the nodes don't get drawn. Even though the code that sets the StateImageIndex is getting executed. I assume that I must do all the node drawing myself as well? Does anyone have an example they can show me?

Is there a *.dll net 4.0 library that reads QR codes for webcams in C# ?

dongtrien — Fri, 25 Jun 2021 02:05:23 GMT

Almost all libraries that read QR codes via webcam use net 4.5 or higher. I want to find a QR code reader library with net version 4.0 ?

How do I update the Keys in the app.config file at runtime ?

dongtrien — Thu, 17 Jun 2021 04:22:47 GMT

I found some code examples that update the keys in the app.config file when running without error and not updating, why the code does not update, see my code

file app.config


<?xml version="1.0" encoding="utf-8" ?>
<configuration>
 
  <appSettings>	
    <add key="FormatImage" value="Jpg" />        
    <add key="LogFile" value="C:\Windows\Log" />    
 
  </appSettings>    
 
</configuration>


private void cmdUpdate_Click(object sender, EventArgs e)
        {
            EditAppSetting("LogFile", "D:\Office2010");
        }
 
 
public static void EditAppSetting(string key, string value)
        {
            try
            {
                System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
                config.AppSettings.Settings[key].Value = value;
                config.Save(ConfigurationSaveMode.Modified);
                ConfigurationManager.RefreshSection("appSettings");
            }
            catch (Exception ex)
            {               
                MessageBox.Show("Error update file App.config: " + ex.Message, "Thông báo kiểm tra !", MessageBoxButtons.OK, MessageBoxIcon.Question);
            }
        }

Regex Class library class declaration error ?

dongtrien — Wed, 16 Jun 2021 03:48:43 GMT

In the program to convert Vietnamese from accented to unsigned in C#, use the code in:

https://www.dtmi.net/chuyen-tieng-viet-co-dau-sang-khong-dau-trong-c-javascript-php-va-sql-server/
https://docs.microsoft.com/en-us/dotnet/api/system.text.regularexpressions.regex?view=net-5.0

I declare the library using System.Text.RegularExpressions; and added the library System.Text.RegularExpressions.dll but still got the error like in the picture https://www.mediafire.com/file/fwmaqggcv5ik7ct/err03Regex.jpg/file

Where does the My Settings store the data

THIEF15 — Mon, 07 Jun 2021 23:14:02 GMT

I recently learned that you can use My.Settings.storemydata to save data but where does it save the data to? It isn't in the .exe file because if I change the filename or the location of the .exe it can't load back the saved data. So where is it stored then?

Generate QR code in Devexpress can't use lowercase ?

dongtrien — Fri, 21 May 2021 04:03:44 GMT

Can't use lowercase letters in Devexpress to generate QR codes? Or is there a library called that can generate lowercase uppercase QR codes with less error ?

App.Previnstance

Ian Brooke — Mon, 18 May 2020 14:29:54 GMT

Can anyone answer a couple of questions for me?

1. What exactly does app.previnstance check? I know what it does, I need to know exactly how it does it. Is it using a mutex?

2. Can anyone suggest what could cause app.previnstance to fail and by fail I mean say there is a previous instance running when the previous one should have, and appears to have, ended.

Thanks

Stay well away from a "program" called RESTORO

Michael Newman — Fri, 19 Feb 2021 09:10:21 GMT

A general word of warning to those who have experienced application activation problems with windows. A search on the web listed RESTORO as a program that would resolve this problem. IT DOES NOT!. In fact it just fills your entire windows operating system with 48 items of malware and you are charged for the privilege. When requesting assistance, all you get is an automated response acknowledging your email but no reply to your query.

The malware infestation was so bad that I had to reformat my entire hard drive and start all over. Perhaps I should consider myself lucky that it was a brand new OS installation without any programs or worse still, years of work.

Stay well away from these parasites.

I hope this will protect others from being caught

Visual Studio 2019 Community Edition

Michael Newman — Thu, 11 Feb 2021 12:09:01 GMT

For many years I have been using Visual Studio 2013 Professional on Windows 7 and it worked perfectly. Unfortunately that computer died and I had to go to Windows 10. I downloaded and installed VS 2019 Community Edition and have been trying to use it but what a disappointment. It is about as fast as a donkey with 1 leg and an overdose of heart failure.

It seems to take forever to create a new project, at least 30 seconds. With something as simple as a button on the form that shows a message box with the word "Hello" in it, takes another 30 seconds or more to compile.

Is this progress for Microsoft or have I done something seriously wrong?

Update SQL DB then update TOTALS

John Etling — Fri, 18 Dec 2020 15:11:37 GMT

I will attempt to explain my issue as clearly as possible:

GOAL: After inputting a value in a text box that value writes to the DB

Once value is written, the value needs to be added to another column (INVOICE_TOTAL) in the DB then updated on the form.

If a specific checkbox is checked, the input value also needs to write to a second column in the DB (WARRANTY_TOTAL) then updated on the form.

use as few open close SQL connections as possible.

EXAMPLE: User inputs 1200.00 in the TruckRepairCost textbox. Both the TruckRepairCost and InvoiceTotal textboxes then should reflect the 1200.00.

User then inputs 300.00 into the TrailerRepairCost textbox.

InvoiceTotal textbox now reads 1500.00, TruckRepairCost textbox shows 1200.00 and TrailerRepairCost textbox shows 300.00

User selects 'Yes' in the warranty repair DropDown box for the trailer repair. WarrantyTotal textbox now should show 300.00, InvoiceTotal should now read 1200.00, TruckRepairCost shows 1200.00 and TrailerRepairCost shows 300.00

PROBLEMS: I am unsure what method to use, as I foolishly tried TextChanged and well, needless to say that did not fair well. I thought MouseLeave maybe? Not sure what proper method to use to invoke the changes.

Because my VB skills are lacking about I am unsure how to work the code with minimal DB connections opening and closing.

I am posting a portion of the relevant code below so you can view my utter mess. Please do not make snide remarks about how poorly the code is. I know it is pitiful but I'm doing the best that my knowledge allows. I am NOT asking for someone to write the code unless one feels compelled to do so. I am asking for direction so I may learn and make the code more efficient. I have tried numerous ideas and scoured the Internet for assistance prior to posting here but finding nothing relevant to my issue.

Private Sub TruckRepairCost_MouseLeave(sender As Object, e As EventArgs) Handles tbTruckRepairCost.MouseLeave
        ' Write value of Truck Repair to DB (unsure if will need to add to existing number. May need: (TRUCK_REPAIR_COST = TRUCK_REPAIR_COST + @upd))
        Try
            cmd.Parameters.Clear()
            cmd.CommandType = CommandType.Text
            cmd.CommandText = ("UPDATE Maintenance_Table 
                               SET TRUCK_REPAIR_COST = @upd
                             WHERE PETS_LOAD_NUMBER = @ln")

            cmd.Parameters.AddWithValue("@upd", tbTruckRepairCost.Text)
            cmd.Parameters.AddWithValue("@ln", tbPetLoadNumb.Text)

            cmd.CommandType = CommandType.Text
            cmd.Connection = New SqlConnection With {
                   .ConnectionString = My.MySettings.Default.PETS_DatabaseConnectionString
             }
            cmd.Connection.Open()
            cmd.ExecuteNonQuery()
            cmd.Connection.Close()

        Catch ex As Exception
            'If a calculation error occurs, show Error message box
            Dim frm As New MeMsgCalcError(ex, "'Truck Repair Cost' DB Write Error." & vbCrLf & "Lines 126-148")
            frm.Show()
        End Try

        Dim a, b As Decimal
        ' If warranty checkbox is checked, also write the value of tbTruckRepairCost.Text to the Warranty Column of the DB
        Try
            b = CDec(IIf(tbTruckRepairCost.Text.Trim = "", 0D, tbTruckRepairCost.Text.Trim))

            If cbTrkMaintWarranty.Text = "No" Or cbTrkMaintWarranty.Text = "N / A" Then
                tbTruckRepairCost.Text = b.ToString("C2")
            ElseIf cbTrkMaintWarranty.Text = "Yes" Then
                a = b
                tbTruckRepairCost.Text = b.ToString("C2")

                Try
                    Select Case True
                        Case a > 0D
                            cmd.Parameters.Clear()
                            cmd.CommandType = CommandType.Text
                            cmd.CommandText = ("UPDATE Maintenance_Table 
                                                   SET WARRANTY_TOTAL = WARRANTY_TOTAL + @upd
                                                 WHERE PETS_LOAD_NUMBER = @ln")

                            cmd.Parameters.AddWithValue("@upd", a)
                            cmd.Parameters.AddWithValue("@ln", tbPetLoadNumb.Text)

                            cmd.CommandType = CommandType.Text
                            cmd.Connection = New SqlConnection With {
                                   .ConnectionString = My.MySettings.Default.PETS_DatabaseConnectionString
                             }
                            cmd.Connection.Open()
                            cmd.ExecuteNonQuery()
                            cmd.Connection.Close()

                        Case Else
                            Exit Sub
                    End Select

                Catch ex As Exception
                    MessageBox.Show(ex.Message)
                End Try
            End If

        Catch ex As Exception
            'If a calculation error occurs, show Error message box
            Dim frm As New MeMsgCalcError(ex, "'Truck Repair Warranty' DB write Error." & vbCrLf & "Lines 161-189")
            frm.Show()
        End Try

        Calc()
    End Sub

Private Sub Calc()
        If tbPetLoadNumb.Text.Length = 0 Then
            Exit Sub
        End If

        Dim cmd As New SqlCommand
        Dim reader As SqlDataReader

        Try
            cmd.Parameters.Clear()
            ' Get running total of the REPAIR total first followed by a running total of the Warranty Total
            cmd.CommandText = "SELECT SUM(IsNull(APU_PM_COST, 0)
                                        + IsNull(APU_REPAIR_COST, 0)
                                        + IsNull(BODY_REPAIR_COST, 0)
                                        + IsNull(TOW_COST, 0)
                                        + IsNull(TRAILER_REPAIR_COST, 0)
                                        + IsNull(TRUCK_REPAIR_COST, 0)
                                        + IsNull(TRUCK_PM_COST, 0)
                                        - IsNull(WARRANTY_TOTAL, 0))
                                 FROM Maintenance_Table
                                WHERE PETS_LOAD_NUMBER = @ln

                                UNION
              
                               SELECT IsNull(WARRANTY_TOTAL, 0)
                                 FROM Maintenance_Table
                                WHERE PETS_LOAD_NUMBER = @ln"

            cmd.Parameters.AddWithValue("@ln", tbPetLoadNumb.Text)

            cmd.CommandType = CommandType.Text
            cmd.Connection = New SqlConnection With {
                .ConnectionString = My.MySettings.Default.PETS_DatabaseConnectionString
            }
            cmd.Connection.Open()

            Try
                reader = cmd.ExecuteReader()
                Dim Cost As Decimal
                Dim Warranty As Decimal

                With reader
                    .Read()

                    'Both must be GetDecimal(0) as only one result per SELECT is returned.
                    Cost = .GetDecimal(0)
                    Warranty = .GetDecimal(0)

                    tbInvoiceTotal.Text = CStr(Cost)
                    tbWarrantyTotal.Text = CStr(Warranty)

                    Return

                End With

                reader.Close()

            Catch ex As Exception
                'If a calculation error occurs, show Error message box
                Dim frm As New MeMsgCalcError(ex, "'Invoice and Warranty Total' Calculation Error." & vbCrLf & "Lines 127-178")
                frm.Show()
            End Try

        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try
        cmd.Connection.Close()
    End Sub

Error generating Win32 resource: The process cannot access the file because it is being used by another process ?

dongtrien — Mon, 09 Nov 2020 01:28:16 GMT

Report errors in Winform of Visual Studio when pressing the Rebuild button ... Error generating Win32 resource: The process cannot access the file because it is being used by another process. How is this error fixed ?