System.NullReferenceException was unhandled
Message=Object reference not set to an instance of an object.
Source=Image Invoice Management
[Code]......
i do understand that the list count is 0 so shouldn't it be declairing Start_Pos = 0
i have a code that grabs an image from a site, this works fine and it does get the image fine, but every now and again my internet runs slow and it takes a while for the image to pop up thus causing the error:[code]How would i make it display the msgbox if it returns NullReferenceException error ?
View 9 Repliesi have a small problem with my code that only happens every now and again.Im using multi threading on this and every now and again i get this error: System.NullReferenceException was unhandled Message="Object reference not set to an instance of an object."
Some times the program completes perfect with no errors and sometimes i get the above error.When i get the error there is always 1 item left in the list but when it completes perfect no items are left.Again this error does not appear every time, only every now and again. For example i had to run my program like 20 time to get this error, 19 times it worked perfect with no errors and 1 time with this error.
i have this code in my btnsave..it can detect conflicts but after that a dialog box saying: An unhandled exception of type 'System.NullReferenceException' occurred in AppointmentSchedulingClient.exe
Additional information: Object reference not set to an instance of an object. and it points to the green one below.
If Val(cbostart.Text) > Val(cboend.Text) Or Val(cbostart.Text) = Val(cboend.Text) Then
MsgBox("Error in time.", MsgBoxStyle.Information, "MESSAGE")
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An unhandled exception of type 'System.StackOverflowException' occurred in System.Windows.Forms.dll it also says make sure you do not have infinate loop or infinate recursion il give all code in order that they are executed in Check the chechbox and it disables all irelevent stuff and populates the combobox
Private Sub CheckBox_Spray_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox_Spray.CheckedChanged
If Me.CheckBox_Spray.Checked = True Then
[code]....
I have been trying to figure out the source of error in my application. What this function (GetConcentrations()) is to display data from my database onto a DataGridView. The function is called in the PageLoad but works fine but when I call it in another Sub, I get this error.
Here is the code:
Private Sub GetConcentrations()
Dim conString As String = ConfigurationManager.ConnectionStrings("dbAsthmaConnectionString").ConnectionString
Me.dataAdapter = New SqlDataAdapter("Select * from tblConcentrations", conString)
[code]....
When I run my project I get "An unhandled exception of type 'System.StackOverflowException' occurred in System.Windows.Forms.dll"
Public Class frmViewReport
Dim objForm As New frmViewReport
Private Sub frmViewReport_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
objForm.ViewReport("C:a2.rtp", , "@parameter1=test�mter2=10")
[code]....
I keep getting an eroor this error says: An unhandled exception of type 'System.ArgumentOutOfRangeException' occurred in system.windows.forms.dll Additional information: Specified argument was out of the range of valid values.
Option Strict On
Public Class frmWeeklyReport
Inherits System.Windows.Forms.Form
[code].....
I always get this error during the Paint event: System.AccessViolationException was unhandled. The weird thing is that it doesn't happen the first time it goes through.
Here's the code.
Friend CustomFont As Font = GetCustomFont()
Private Function GetCustomFont() As Drawing.Font
Try
Dim PFC As Drawing.Text.PrivateFontCollection
[CODE]...
Symbols is just a 2 dimensional array of characters.
This never happened to me, and the less data one has (usually) the less you can say what happened.I am trying to write a simple query analyser. I randomly receive these kind of crashes:
[Code]...
The file specified above does not exist. The place where it crashes is wrapped with Try-End Try. Moreover, yes, I have the painting event set up but it should not concern it (or maybe it does?). I have to add that I use visual basic express edition. The error occurs ocasionally - sometimes when I'm lucky nothing happens, and when I'm not then I get this crash.
vb
Imports System.Windows.Forms.HtmlDocument
Public Class test_vbdotnet
Private Sub runtime()
[Code].....
I want VB.NET to get access to the innerText and make a if statement out of it. But it always returns error. (see the comments for details.)
This is driving me slighty madder than i usually am. The thing thats bugging me is the EXACT same code works in a test project i did with an sdf database.See my comments in the code
vb Private Sub tbScan_KeyUp(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles tbScan.KeyUp
[Code]...
I have made a tic tac toe board and when i go to debug the application i get a "NullReferenceException was unhandled".
this happens diring this part of the code:
Dim x As Integer = Val(index.Chars(0))
I am getting a NullReferenceException was unhandled error when i run my debugging in this part of my code: Dim x As Integer = Val(index.Chars(0))
what can i do so this will stop and my program will work?
on Form1, i have a combobox1 where i have 15 values. im using a case statement with those 15 values to decide what is the next form to go to. i need to make sure the user cannot add in his own text to it or click the NEXT button without having any value at all. how do i add these "exceptions" to my code?
i would think any exception would go before the case so that it could tell you didnt put in the right answer before it looks through the case statment and give you a nullexceptionhandler reference.
I am working on my project with the listbox, I am reading the strings through the text file and split the strings to input them on the listbox.[code]When I selected the item on the listbox, I get the error.Error: Object variable or With block variable not set.
View 11 RepliesPrivate
Sub cmdExit_Click(ByVal
sender As System.Object,
ByVal e
[code]....
I can't work out what's causing it. The error report says "Object variable or With block variable not set." for the line "allSlotLabels(i).Image = imgCherries". This line is no different from the other, so I guess it's just the error it picked up first after randomly generating the number.
[Code]...
Using Visual Basic 2008 Express Edition, and trying to set up code for an Add button to add a row to an SQL database. The code below is copied from the Help, and modified to reflect the fact my dataset is called Test_SQL_DbDataSet, my table is called Details, and just 2 columns at the moment .. "ID" and "Detail"
Dim newDetailsRow As DataRow = Test_SQL_DbDataSet.Tables("Details").NewRow()
newDetailsRow("ID") = "10"
newDetailsRow("Detail") = "Maint"
Test_SQL_DbDataSet.Tables("Details").Rows.Add(newDetailsRow)
When I select it, I get a "NullReferenceException was unhandled" error saying "Object reference not set to an instance of an object"
I have the follwing codewhich transfer the value from NumericUpDown64 to the array Conc(0,0) which is part of the structure USerInput:
UserInput.Conc(0, 0) = NumericUpDown64.Value
When I run the program I recieve the NullReferenceException was unhandled. Object reference not set to an instance of an object.
Im getting an Error saying:"NullReferenceException was Unhandled - Object reference not set to an instance of an object."I have no idea what this means as a beginner,
Me.FilmTableTableAdapter.Fill(Me.DVDDatabaseDataSet.FilmTable)
Dim con As OleDb.OleDbConnection = New OleDb.OleDbConnection("Provider=Microsoft.jet.oledb.4.0;data source=|DataDirectory|\DVDDatabase.mdb")
Dim cmd As OleDb.OleDbCommand = New OleDb.OleDbCommand("SELECT * FROM FilmTable", con)
con.Open()
[Code]...
I got two forms.
Form 1 I ask the user a number of guest
Form 2 I ask each guest their name, their age
I decide to make a loop throught form2 array base on the number of guest but then I got this error. NullReferenceException was unhandled.
Private Sub btnBook_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnBook.Click
iTest = CInt(txtChildren.Text)
Do Until (iCounter = iTest) And (bIsNextClicked = True)
PassengersDetails(iCounter).ShowDialog()
Loop
End Sub
I am new to vb.net 2005 and am desperate in need of solution as I faced error on the following codes.
Public Class Form1
Private PreviousTab As TabControl
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Me.Load
[Code].....
Private Sub btnSendMsg_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSendMsg.Click
Dim con As New OleDb.OleDbConnection
[code].....
I'm try to use NATUPNPLib to use UPnP to do and automatic port forward in my router but I keep getting and error that I'm not sure how to handle.Here's the part of the code with the error.
Imports NATUPNPLib
Imports UPNPLib
Public Class Form1
[code].....
I've tried making sure Windows 7 has Network Discovery on and that UPnP in enabled in my router, could it just be my router and how it handles UPnP?
I am slowly getting used to working with classes and for the most part am getting things to work. This problem has me stumped though. Below is an abbreviated version of the code. The form class is:
HTML
Public Class Form1
Private Lines As New List(Of DblLine)
[code].....
Debugging Error "NullReferenceException Was Unhandled'. I have the following code on my form
[code]...
Error occuring at line: SqlDataSource3.UpdateParameters("TechID").DefaultValue() = CInt(technicianRow("TechID"))
Here is full VB code:
[code]....
[code] this is my code n i want to store data at runtime in the my database.i used data base as an access07 and my platform is vb.net..Now come to the point when i run the project it terminates when i'm inserting my data in the access file.[code]
View 4 RepliesMy code
Dim pointer As Integer, index As Integer
For pointer = 1 To 6
For index = 0 To 5999
[CODE]...
All i get is an error message saying NullReferenceException was unhandled the bold part is were it says the error is
