Assign Data To An Array From A Text Box - Null Reference?
Apr 24, 2011when i try to assign data to an array from a text box, i get a null reference exception, stating "Object reference not set to an instance of an object".
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Null Reference Exception Unhandled Error When Input Is Saved Into Array After Array Has Been Erased?
Jun 23, 2011n 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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Null Reference Exception While Trying To Initialise An Integer Array?
May 15, 2011I 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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Office Automation :: Null Reference Exception On A Byte Array
Dec 28, 2011I'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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Assign A Specific Position Across The Line To Have The Printer Print The Data At Without Left Padding The Array Data?
Jul 6, 2011Ypos = TopMargin + Count * PrintFont.GetHeight(ev.Graphics)
ev.Graphics.DrawString(ROData(x, 3), PrintFont, Brushes.Black, LeftMargin, Ypos, New StringFormat())
Count = Count + CInt(ROData(x, 4))
The above line prints the data contents of the ROData array in position three. I would like to be able to assign a specific position accross the line to have the printer print the data at without left padding the array data.
Database Binding And Data Navigation Project Error - Null Reference?
Mar 4, 2012I am trying not to become intimidated or give up.I created a simple database and added stored procedures to read the data on a Windows form using Visual Basic in VS 2010.First I tried the Data Grid Example and all worked, I was able to view the data using a connection string to call the Stored procedure.I have stepped it up a notch by trying to bind data to form controls and I am getting this error message when I try to navigate through the data.
System.NullReferenceException was unhandled
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Null Reference Exception In Line Checking For Null?
Dec 15, 2011I have a fairly simple piece of code:
Private _PurchaseDelivery as PurchaseDelivery
Protected Overrides Sub InsertItem(ByVal index As Integer, ByVal item As PurchaseDeliveryItem)
[Code]....
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?
Asp.net 1.1 - Assign Null Value To Optional Parameters In .NET 1.1?
Dec 21, 2010I tried DbNull.Value but no luck. How do I assign a default value as null to a string parameter that is null in VB.NET? Its litte strange to see that VB does not have anything like plain null as most of the other languages do. Also what is the difference between null and DbNull and Nothing.
View 3 RepliesHow To Assign The AppDate To NUll Like DBNull
Mar 5, 2010I am not sure why VB makes everything such a pain. I have a fields which stores the date and time in the format required to store in MySQL database
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Now I need to assign the AppDate to NUll like DBNull, but I am not able to do it directly. If I change AppDate to Date then I am not getting the required format.
Assign Null Value To Date/time Variable?
Jun 7, 2011Attempting to convert a possible null value into date/time field. Any easy way ?
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Another Method To Reference The Array And The Member Of The Structure To Get The Data?
Jan 31, 2010I have problems with array of structures.my structures are like this
structure order
xxxxxxxxxxx
yyyyyyyyyy
zzzzzzzzzzz
end structure
and then I created many array of structures, like this private arrayorder (100) as order
now i need to sort the entire xxxxxx member of the array of the structure with a function, but I dont want to use loops with arrays indexes to access the information. I want to know if there is another method to reference the array and the member of the structure to get the data.
Assign A Value To Nullable Integer Via A Ternary Operator / It Can't Become Null
Apr 19, 2012If you assign a value to a nullable integer via a ternary operator, it can't become null..While this question may seem like a duplicate of many, it is actually being asked for a specific reason.Take this code, for example: Dim n As Integer? = If(True, Nothing, 1) In that code, the ternary expression should be returning Nothing, but it's setting n to 0. If this were C#, I could say default(int?) and it would work perfectly. Now it looks like I am going to have to ditch the ternary and use a regular If block, but I really want to use the ternary. If Nothing were truly VB.NET's equivalent to C#'s default, how can you explain this behavior?
View 1 RepliesNULL DateTimePicker Text, If There Is No Data
Jan 7, 2010I have about 7 different DateTimePickers that I populate with data from my database. In my database there are Date fields that are actually NULL like a date hasn't been set. I have allowed for this to happen but every time I load up the information into the DateTimePickers, a default date appears even if no data is there in the database. If there is no data, I want the DateTimePickers text to be nothing. Is there anyway around this annoying problem?
View 11 RepliesAssign DBNull.Value To A Variable, Or Write NULL To MSSQL Database?
Dec 3, 2009I have a little problem regarding the use of DBNull, NULL etc. in VB.net in combination with SQL Server 2k.
More specifically, I want to do something along the lines of this:If x = 0 Then
x = DBNull.Value where x is declared by Dim x as Object. I would rather use Double, but I can't assign DBNull.Value to this, and using Object works quite well, too. But every time I hit this condition, I get an exception: A first chance exception of type 'System.InvalidCastException' occurred in Microsoft.VisualBasic.dll This is not a major show-stopper, since the database value I write x to in the next step, is NULL by default - most of the time! So I need the ability to write NULL to it. If that was not the case, I would have been able to work around this by catching exceptions, I think - but sadly, this isn't really of use then.
Combo Box Selected Item Is Null - Assign An Empty String To It Instead?
Dec 9, 2011I have a property called ReplacementTo and I set a value to it based on the selecteditem from the combobox, like this:
classEquipmentItem.ReplacementTo = cmbReplcmnt.SelectedItem.ToString
Now I can't use cmbReplcmnt.Text because what I actually need is the value of that SelectedItem
So problem is, if the user leaves the combobox as blank, it throws a null exception.I decided to use the IIf function then:classEquipmentItem.ReplacementTo = IIf(IsNothing(cmbReplcmnt.SelectedItem.ToString), classEquipmentItem.ReplacementTo = "", cmbReplcmnt.SelectedItem.ToString)
Unfortunately I still get the error I tried using a Try-Catch for it and it worked, but I don't want to rely on the Try-Catch, so I was wondering is there a another way to work this through?
Assign Events Dynamically With A Form That Has No Reference?
Jun 19, 2012I've got a class where I pass in a panel reference and in that panel I'm then required to draw multiple other panels that represent my objects. The issue is that when I go to bind dynamically click events to these panels I don't have reference to the Form of which I want to popup on the click event.
The reason for this structure is so that I can redraw my class dynamically and reattach certain events to each object.
Is there any way to do this without moving my classes logic outside of the Assembly or is there any way to attach my click event to a piece of code logic to a sub in my WinForm?
Pulling SQL Data Into Text File - Some Fields Null / Blank
Apr 2, 2010I am trying to pull sql data into a text file. The code works just fine, until some new data comes in from lazy employees and a couple fields (used for notes/comments) are now left blank. Originally I've never seen them blank so I didn't think anything of it.
col2 = myreader.GetString(1)
It will error if the field is ever null - I even tried using a case when:
case when note is null then '" & empty & "' else note end and set the variable emtpy = '', but vb still thinks that it's null and errors?
.net - Null Reference But It's Not?
Jun 2, 2010This is related to my previous question but it is a different problem.I have two classes: Server and Database.
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The problem is in the LoadTables in the Server class. When it hits Databases.Add(db) it gives me a NullReference error (Object reference not set). I don't understand how it is getting that, all the objects are set.
Null Check Always Returns Null, If Removed Returns Object Reference Not Set To An Instance Of An Object
Jun 24, 2010I have some code which gets child items for a menu via the GetChildren function which takes a list of menuData: Dim builtMenu As New List(Of MenuData)(_rawData.FindAll(Function(item) item.GroupingID = 0))
For Each menuData As MenuData In builtMenu
If menuData.Children IsNot Nothing Then
menuData.Children.AddRange(GetChildren(menuData))
End If
Next
If I check if menudata.children isnot nothing, it always is nothing because the GetChildren function is yet to run (providing the child items, which do exist). If I remove this check and just have this code:
Dim builtMenu As New List(Of MenuData)(_rawData.FindAll(Function(item) item.GroupingID = 0))
For Each menuData As MenuData In builtMenu
menuData.Children.AddRange(GetChildren(menuData))
Next
Then I am presented with a Object reference not set to an instance of an object error on menuData.Children.AddRange(GetChildren(menuData))
How To Avoid A Null Reference
Jan 8, 2011I have been trying to use sockets in VB.NET and once I cannot understand how to avoid a null reference. [code] I have tried introducing sock as 'New Socket', but this gives me 'Overload resolution failed because no accessible New can accept this number of arguments'.I also cannot simply add '= Nothing' onto the end of my declaration since this still gives a null reference.
View 6 RepliesNull Reference Exceptions
Jan 29, 2011I'm practicing on this one, and I know it would be better to just use a string variable instead of a class. I have another working program using a string variable, but on this one I wanted to make it use an array of class objects.
I keep getting null reference exceptions at the line where the object is assigned the textbox text.[code...]
Null Reference From KeyDown?
Dec 16, 2010How do I check for a null object in a subroutine handle?
Private Sub Form1_KeyDown( _
ByVal sender As Object, _
ByVal e As System.Windows.Forms.KeyEventArgs) _
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Null Reference With An Interface?
Mar 21, 2011I have a null reference warning. Dummy code as follows:
Dim poo As IEnumPooTypes
Toilet.GetPooInBowl(poo)
The variable 'Poo' says it may result in an object reference not set error but I cannot use the 'New' keyword with an instance. How do I make the warning go away?
Why Null Reference Exception
Jun 27, 2012visual 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 RepliesXML Null Reference Error?
Jan 4, 2010Im trying to write code that will insert 'records' into an xml file, but everytime i click the button to make the changes to the XML file, it throws a null reference exception, ive gone through this code must be 100 times and cannot find what needs to be declared as 'new' as i know nodes can't be 'new' and the doc is 'new'
Imports System.Xml
Public Class frmuseradmin
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.net - Null Reference Exception DNN Core 5.6.3
Jul 26, 2011My 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
[code]....
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)?
.NET - Null Reference Exception Was Unhandled
Mar 7, 2011I 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
[code]....
Asp.net - Net Null Reference On Database Connection?
Jun 13, 2012I know I'm being an idiot here and I just can't work it out. But i'm trying to take some data back from a vb.net database. It's falling over with a Object reference not set to an instance of an object error. And before the code runs it's saying the variable is being used before it's set, but I can't see how. Code:
Private taNotifications As dsDataTableAdapters.NotificationsTableAdapter = New dsDataTableAdapters.NotificationsTableAdapter
Dim notification As dsData.NotificationsDataTable = taNotifications.GetDataByClientID(userrow.UserID)
If notification.Rows.Count > 0 Then
Dim notificationrow As dsData.NotificationsRow
Dim forwardURL As String = notificationrow.ForwardLocation
End If
It falls over on the Dim forwardURL As String = notificationrow.ForwardLocation
C# - P/Invoke On X64 Null Reference Exceptions
Feb 24, 2010P/Invoke on x64 null reference exceptions, I get null reference exceptions when I try to compile for x64 in .NET code that makes use of platform invocation services to call unmanaged code in dlls. Am I missing something obvious here?
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Getting A Null Reference Exception W/program?
Jul 19, 2009I 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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