I've converted an application for connecting to a vpn server and starting a remote desktop connection from vb6 to vb.net. But now when I'm trying to run the program I get an ArgumentNullException I've tried searching for a solution but I've been unable to find one. Below is my code:
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n my project i am to enter a name and a test mark into two separate text boxes and then select the button to store the information into the arrays, one array for names and another for marks, but when it is reset using the Erase <Array> fuction andi try to re enter information, no matter what information is entered i get a "Null Reference Exception Unhandled" Error.I am using Visual Basic 2008.My code is as it says from now:
Public Class frmAdverageTestMarkCalculator
Dim ClosingMsg As String
Dim Closingtitle As String
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I am getting System.NullReferenceException:Object reference not set to an instance of an objectwhile executing the below code..!!
Dim arr() As Integer
Dim g,j As Integer
g=10
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I have a fairly simple piece of code:
Private _PurchaseDelivery as PurchaseDelivery
Protected Overrides Sub InsertItem(ByVal index As Integer, ByVal item As PurchaseDeliveryItem)
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Which is inside a class which overrides a custom list base. The code is occassionaly throwing an unhandled exception, System.NullReferenceException, on this line when used in production:
If _PurchaseDelivery IsNot Nothing AndAlso _PurchaseDelivery.DefaultSKUBinID.HasValue Then
DeafultSKUBinID is declared as an Integer? (Nullable Int) in the PurchaseDelivery class. I cannot see what might be causing this error, why would this be returning an error?
So I've been trying to write an Add-In for Excel for a week now. I already have the add-in made up in VBA (CustomUI.xml has been added too for a ribbon). I've been using it for awhile now from Excel's VBA Editor. But I want to get a bit more fancy with it, so I'm going to re-write it in VB.net since it's ribbon designer is nicer than writing XML code by hand. The only problem is, I've been very confused on how Visual Studio sets up all the references to Excel.As I've been looking through examples in threads across this forum I see a lot of people using this code to get access to Excel.
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at the top of every sub routine that I'm going to be using excel in? Isn't that going to open a bunch of different windows and separate my code from the data I'm trying to manipulate?
Edit by Moderator: [URL]...I know this thread is extremely old but it applies to my situation.Using Visual Studio 2008, VB, I get an error in this code:
Code:
Dim strWorkbkName As String
Dim strWorkshtName As String
Dim XlApp As Object
Set XlApp = GetObject(, "Excel.application")
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not reply to threads which have been inactive for more than one month and please start your own threads to ask your own questions. Since you question is about VB.Net, I have moved your thread from the Office VBA forum to the .Net Office Automation forum.
The problem with the following code is that the object oWB is visible and initialized in Form2, but when I show SaveDialog1, the object gives a NullReferenceException. I already know, because I checked in the debugger, that oWB has a valid reference when I leave Form2 and also when I come back from Form2. So I am sure the problem is that the reference simply is not visible in SaveDialog1 for some reason. So please don't tell me that the initialization of oWB returned a Nothing reference because I know it did not.
I get a NullReferenceException on the following line:
Form2.oWB.Save()
I researched this for a whole day and came up with a Microsoft article that explains that it is necessary to run each form of a .NET COM application on its own thread. It gave some code to accomplish this. I incorporated this code into my program. But I still have the NullReferenceException.
Simplified version of Code with most processing deleted below:
Public Class Form2
'Define Microsoft Excel Objects
Dim oXL As Excel.Application
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What I'm trying to do is create an excel chart in a spreadsheet that I've just created using VB.Net code. I get the spreadsheet and chart created fine but then I get this error. An unhandled exception of type 'System.MissingMemberException' occurred in microsoft.visualbasic.dll. Additional information: Public member 'xlColumnClustered' on type 'Integer' not found. [Code]
View 1 RepliesError: System.Runtime.InteropServices.COMException (0x800A03EC): Exception from HRESULT: 0x800A03EC is thrown after execeution of Microsoft.Office.Interop.Excel.ApplicationClass.set_Calculation(XlCalc ulation RHS)
Out of nowhere COM start throwing exception when I set change excel's Calculation property. Line of code that followed set_Calculation was.Workbooks._Open. This used to cause exception every second try. Than I changed order, first open workbook and than set calculation property. Amount of exceptions start decreasing than I added thread.sleep(200) and exception is not thrown anymore. This happens only on one some of user machines while others are fine.Application itself is single threaded so this delay should be of importance if and only if set_Calculation is executed asynchronously. What I'm missing here?
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I have a windows form application in Vb 2008 pulling data off SQL Server 2005. I need to be able to create an Excel report on the fly and dump the results from a query onto the first Excel sheet. After that I run another query and need to dump the results to the next sheet in the same workbook. Problem is that this query may spit back more that 65356 rows. Therefore I need to put the first 65000 rows in the second sheet and then the rest in the next sheet and so on and so forth.
Unfortunately, when I fix the sheet_var = 2 to start dumping in the second sheet, I get an index error. Invalid index. (Exception from HRESULT: 0x8002000B (DISP_E_BADINDEX))
The error is occuring in this line: oSheet = obook.Worksheets.Add(After:=obook.Worksheets("Page " & sheet_count))
Here is the code:
Code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Cursor.Current = System.Windows.Forms.Cursors.WaitCursor
Dim cnn As SqlConnection
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visual basic application prompting me a message "Object reference not set to an instance of an object". i have 2 project in one solution. One is developed in c# and other is in vb. i am calling a method of c# project in vb project. the vb code is:[code]when i debug vb project individually it works properly and when i call vb application from c# application, it prompting error. is i missed out any .net framework reference? [code]
View 1 RepliesMy site has been running fine for sometime now until recently I see in the event viewer a null reference exception in the DNN core:
DotNetNuke.Common.Globals.GetStatus() in
F:BuildsMaintenanceWorkingDirectoryLibraryCommonGlobals.vb:line
1125 at DotNetNuke.Common.Initialize.InitializeApp(HttpApplication
app) in
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the line 1125 is:
_Status = UpgradeStatus.None
Which is a property of the Globals class and an Enum Also when this happens it doesnt just do it once then sort its self it does it roughly every minute for an hour or so.I made sure all dataprovider.instances are either in a using or a try catch finally or self closing(if the reader is not used)?
I have the following code, which is meant to loop through a list of CheckBoxes and if checked if gets the text contained in the linked textbox through the tag of the Checkbox, i have used it before and it worked fine but this time i am getting the following error:
Null Reference Exception was unhandled
Dim DisCheckBox As CheckBox() = {chk0_6, chk6_12, chk12_18, chk18_24, chk2_3, chk3_4, chk4_5, chkXSB, chkSB, chkMB, chkLB, chkXLB, chkS, chkM, chkL, chkXL, chkXXL, chkXXXL, chkXXXXL, chkW8, chkW10, chkW12, chkW14, chkW16, chkW18, chkW20}
For Each Chk In DisCheckBox
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I keep getting a null reference exception w/this program, and its on the line that declares the array. I've looked it over and over and I just don't see why... Can you let me know if you see anything obvious? I'm also getting an "index out of range" exception, but it looks right to me...I declared everything with an 11 for 12 months, 0 to 11 for the intcount.
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If Not obj is Nothing and obj.IsActive Then ' null reference exception??constructions like this in C# works, because obj.IsActive is not checked if the first condition is false...
View 2 Repliesi have this sql transaction i am using to make sales.But when ever i run the code it give me this null reference exception.I do not really know what is wrong.
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Now, when I try to debug my program, it immediately throws the exception below, this is before entering the program itself if I understand correctly. Any advice on how to resolve this? Between now and the last time I tried running debug, I had tried making a section of the program MDI, but gave up on that and delete that code. Also none of that part of the program is even in a position to be ran (the initial interface and onward do not execute that code)
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I'm currently taking a VB class and i'm having trouble running my program properly.[code]
View 3 Repliesstarted learning vb.net..encountered this problem in this code: Private Sub NavigateRecords()
TextBox1.Text = ds.Tables("stdDataSet").Rows(inc).Item(0)-error msg appeared here sayin null reference evception was unhandled. Object reference not set to an instance of an object.
TextBox2.Text = ds.Tables("stdDataSet").Rows(inc).Item(1)
TextBox3.Text = ds.Tables("stdDataSet").Rows(inc).Item(2)
TextBox4.Text = ds.Tables("stdDataSet").Rows(inc).Item(3)
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write know i am gettin null reference exception due to followin code
Imports System.Xml
Imports System.IO
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in the ReadFile() Sub, if the user tries to read a file that is not there he gets an exception
which results in the 2nd line in the Catch being executed. So far so good. But the 2nd line of
code in the mnuOpen_Click then gets a System.NullReferenceException which I don't understand since
the mnuOpen_Click code all works fine when called from the Open menu item. The exception
information suggests I use the "new" keyword to create an object instance, but in all my reading
and all the different ways I've applied the keyword New to the code, I've not been able to figure
out how to do this.[code...]
i keep getting this null reference exception error and i can't figure out what i need to do to fix it. I have this in the form
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keep getting this null reference exception error and i can't figure out what i need to do to fix it.I have this in the form
Private Sub cbLookUp_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cbLookUp.Click
Dim webDownload As New Net.WebClient
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I have formulas in certain cells and happens to be part of the Excel range that I pull into a vb.net array and when I write the array back out to the Excel Range, I loose all the formulas in it.Is there an option to retain formulas in a .net array?
View 3 RepliesI'm using vb.net and sql server 2000 for developing my application....The problem i'm having is the Null Reference Exception on the Following line of code:
Dim cmd5 As New SqlCommand("select crtns_removed, pieces_removed, scheme from Outgoing_Invoice where invoice_no = '" & Me.ComboBox5.SelectedItem.ToString.Trim & "' And category = '" & Me.ComboBox1.SelectedItem.ToString.Trim & "' and item_name = '" &
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Public Class Form1
Dim int As Integer = 0
Dim CustomerTable As New DataTable
Dim instance As New InvalidOperationException()
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This is the code this exception occurs when i click on the home button of my webbrowser.or i enter any site on the combobox.
I get a warning message that reads " Variable 'cust' is used before it has been assigned a value. A null reference exception could result at run time.", but it occurs in my vb file "Northwind.vb with the following code:
Public Class Northwind
Private cust As BizObjects1.Customer
Private Sub frmCustomer_Load( _
ByVal sender As System.Object, _
ByVal e As System.EventArgs) _
Handles MyBase.Load
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I'm trying to catch an invalid entry in a textbox that I use to enter numbers using the subroutine below.
In the Catch blok I want to change the ForeColor of the textbox that contains the invalid entry.
This did function but now gives me a null reference exception on the line where I change the ForeColor.
Private Sub SaveParm()
Dim Temps(2, 2) As Double
Dim Cname As String = "Text0"
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does any one know the reason of why I get Warning in the Finally block in vb.
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Been looking at a lot of post/articles about using Iif(). All of this started when I tried to use IIf() like a conditional operator much in the likes of C/C#/C++ etc.What I tried to do exactly was exactly in the lines of this of the following post:Using VB.NET IIF I get NullReferenceException
However, the solution I had implemented was borrowed from the following msdn site:
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