I'm trying to add objects from a class I created using data from an excel worksheet to a list using a for loop [code]When I run it I receive "System.NullReferenceException was unhandled by user code Message=Object reference not set to an instance of an object."
View 4 RepliesI have a class that has a property that I declare like this:
VB.NET
Private _DirectoryList As List(Of FileDirectoryInfo) ''' <summary> ''' Array of directories. ''' </summary> ''' <value>Object</value> ''' <returns>Directory array list</returns> ''' <remarks>N/A</remarks> Public Property Directory As List(Of FileDirectoryInfo) Get Return _DirectoryList End Get Set(ByVal value As List(Of FileDirectoryInfo)) _DirectoryList = value End Set End Property
[Code]...
i am using VB.net 2003 and i am trying to get the number of rows of a dataset from form1 into form2 in order to use it for something else and i am getting the error"System.NullReferenceException occured...Additional information: object reference not set to an instance of an object"...my code is like this:in form1:Public x as integer= me.dataset.table.rows.count here it gives me the error
in form2:
dim frm as new form1
msgbox(frm.x)
I have recently gotten my hands on a free, open-source IMAP connection API.So far, I have been successful in creating a connection to one of my accounts.Where I'm getting stuck is retrieving folders and/or emails from those folders.Does there happen to be anyone here that is familiar with this API, or even Gmail (particularly the folder structure for IMAP)?
If not, here is a link to the DLL that is listed on sourceforge and the company's website that created it (if you feel like testing):
Koolwired
Sourceforge - Koolwired API
I have created a test account so feel free to use the code below without worrying about username/password issues; I'll just delete it when I'm done with it.Here is the code I have made so far for making a connection:
Dim gSession As New Koolwired.Imap.ImapConnect("imap.gmail.com", 993, True)
Dim gAuthenticate As New Koolwired.Imap.ImapAuthenticate(gSession, "imap_test@serysoft.com", "imap_test")
Try
[code]....
When I run that code, I get an error that states:System.NullReferenceException: Object reference not sent to an instance of an object. (The bold line in the above code).
Now, I'm not sure exactly what that means. Does that mean it tried to access the server and "INBOX" doesn't exist so it gets returned a NULL value? Or is it possibly the coding itself?Maybe the Gmail folder system is weird due to the fact they use labels (even though from what I have read online, the labels act as the folders in the IMAP system).
I got the following code from the demo code samples and just changed the textbox names. But it throws an error:
Private Sub Fill_TextBox()
Dim Num As Integer
Dim DSet As DataSet
[code]....
The error is:
System.NullReferenceException:Object reference not set to an instance of an object.
I am completely new to ASP.NET and VB as well as C#. I am trying to add customers to a contact list out of a DB. Then the list can be referenced to call them up. But when I try to run it I get System.NullReferenceException: Object reference not set to an instance of an object. In line 19.
Here is my code:Page 1 is default page...it connects to the database and grabs the contact information and allows me to select the current contact and add them to a listbox on a separate page:
Imports System.Data
Partial Class _Default
Inherits System.Web.UI.Page
[code]....
The error occurs on line 19 (For Each customerEntry As DictionaryEntry In Customer) in the second set of code from the default2 class.
I'm finishing up working on the high score list of my Jeopardy game. The only problem that I'm running into is when I try to start from scratch without a textfile in the Debug folder.I get a NullReferenceException was unhandled - Object reference not set to an instance of an object. I get this message with the line If (myPlayers.Length - 1) > 2 Then just before I start to compare the scores and reorder the list by score if necessary.I already declared myPlayers as an array of structures in the beginning of the form.
Private myPlayers() As Players
It writes the name and score to the file, but then gives me that error. My goal is to only fill the file with the three players names and their scores.I figured since the file doesn't exist, I'm doing something in that specific code that effects my reference to myPlayers but I can't figure out what exactly. I tried adding
If (myPlayers.Length - 1) > 2 AND File.Exists("highScore.txt") Then
but its still giving me the error.
'read in scores, add scores to file or create new file if neccessary
If File.Exists("highScore.txt") Then
Dim InputFile As StreamReader
[code]....
I am coding in vb.net. At times the data is empty/null this is due to user's input into the db.i will like to bypass it, however i get no luck.here is snippet of my code:
If hct.mydbvalue.name IsNot Nothing Then
dr("mydbvalue") = hct.mydbvalue.name
End If
I still get an error: System.NullReferenceException: Object reference not set to an instance of an object.is there a way if it is a null value to not do anything?
I'm currently building this website which consist of a few webpages.
1.) Login Page
2.) Menu Page
3.) Add Application Page
4.) Search Application Page
My login is working fine, but occasionally when I start to run and debug the prog, it will stop running and point to this error. This is my login page
Partial Class Admin
Inherits System.Web.UI.MasterPage
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim ans As String = Session("Status").ToString()
[code]....
I'm getting System.NullReferenceException error when I try to add the employee info to the Employees list.
[Code]...
I'm having problems with Datagridview Column I have a dataset containing a table called Inventory, which i databound to my datagridview.At my form load event, i set one column's backcolor to blue like this-
dgvBrowseBooks.Columns("Title").DefaultCellStyle.BackColor = Color.
But when i run the program, i get this error "NullReferenceException"- Object reference not set to an instance of an object.
i have this error but i don't one why it appear.. Error: NullReferenceException:{"Object reference not set to an instance of an object."}
[Code]...
The code below is used to check if the application setting, an arraylist is populated or not via the count method.
When running the program fails with error "NullReferenceException was unhandled" as initially the setting (arraylist) will contain no values.In similar circumstances I would declare a new instance of the object or set value to string.empty or check if DBNull.
I know application settings have a save method but to reference/load them one is not needed.I also left the value field in the projects -> settings to be empty.[code]...
I need to be able to add elements to a copy of mylist.testlist without modifying the global mylist object. (Which seems to be happening via the below code.)When I am working on x, which should be a totally separate object, mylist is getting modified as well. How can I fix this? I have worked with lists extensively and never seen this behavior before. I have tested and reproduced the problem in .NET 3.5 and .NET 4.0 on Win 7 Pro 32bit.
Source Code:
Public Class Form1
Public mylist As New test
Sub Main()
[code]....
I have some code that adds items to a List(of Object).
Here's my original code
Dim BeaconStoryList as New List(Of My.StoryType)
Dim BeaconStory as New My.StoryType
Dim NewStories() as New Foriegn.StoryType = GetStories
[Code]....
But as soon as the code assigned "Chicken" to BeaconStory.Title, then BeaconStoryList(0).Title would also change to "Chicken".
With my second version of the code this did not happen.
It's as though it was placing pointers into the elements of the array rather than values. If that is the case, however, then why does my second version of the code work - I'm still passing in the same thing - aren't I?
I am not sure what I'm doing wrong, but I need some guidance from people smarter than me...
View 1 RepliesDoes link text mean I have to return a concrete implementation? Even though I am using svcutil with the /r that includes my entites(where IMyInterface is defined). I get no errors but it changes all List(of IMyInterface) to list(of Object) and I cannot deserialize it on the client
Error: list(of object) cannot be converted to list(of IMyInterface).
I am trying to start the process with the following parameters When I try to start it though I get an System.nullreferenceexception: Object reference not set to an instance of an object
Dim exepath As String = Application.StartupPath + "inffmpeg.exe"
Dim sr As StreamReader
Dim cmd As String = " -i """ + input + """ -ar 22050 -y """ + output + """"
Dim ffmpegOutput As String
[code]....
look after the error i'm having.
module1.vb
Imports System.Data.SqlClient
Module dbconn
[code]....
I have a custom class that all my pages inherit from
Public Class Page : Inherits Page
Private Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
'Display Admin Controls (Buttons) '
If User.Identity.IsAuthenticated Then
[code]....
But for some reason I'm getting this error:
System.NullReferenceException: Object reference not set to an instance of an object.
on this line
If User.Identity.IsAuthenticated Then
This only started happening in IIS7. I have been using this application in IIS6 for over a year without issue, and it's only since I migrated to IIS7 yesterday that this exception started.
i wrote a very simple app and it runs fine on windows xp machines, but on windows 2000 machines... i am getting the following error.. ... nothing showing up in build nor does it happen on xp machines?
************** Exception Text **************System.NullReferenceException: Object reference not set to an instance of an object. at System.Windows.Forms.Control.WaitForWaitHandle(WaitHandle waitHandle) at System.Windows.Forms.Control.MarshaledInvoke(Control caller, Delegate method, Object[] args, Boolean synchronous) at System.Windows.Forms.Control.Invoke(Delegate method, Object[] args) at System.Windows.Forms.Control.Invoke(Delegate method) at
[code]....
When JIT debugging is enabled, any unhandled exceptionwill be sent to the JIT debugger registered on the computerrather than be handled by this dialog box.
I am soooo very new to vb express. i wrote a very simple app and it runs fine on windows xp machines, but on windows 2000 machines. i am getting the following error. nothing showing up in build nor does it happen on xp machines??i have no idea how to fix it!
[Code]...
so I was working on a autoviewer for the site enhanceveiws.net. I have a SmartError Filter in the code. However I got an error. NullReferenceException was unhandled. Object reference not set to an instance of an object. Here is the code.
[Code]....
i'm getting this error whenever i run this page.
My codes: Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim con As String = "Database=barcouncil;Data Source=dev;UserId=root;password=;"
Dim cn As New MySqlConnection
Dim da As New MySqlDataAdapter
[Code]...
I have a problem with a generic list, which consists of intances of a class i created. I am just amazed, each time I add a new object to the list, it overwrites the previous entries. Here is a code sample, i just can't beleive it. I am using visual studio 2010:
Dim translations As List(Of TranslatedValue) = New List(Of TranslatedValue)
If Session("ctlTexts") Is Nothing Then
Dim reader As IDataReader = DataAccessFunctions.db.GetDataReader("SELECT [ControlID], [ControlTextEN], [ControlTextDE], [ControlTextBG] FROM [dbo].[tbLanguage]", GetConnectionString)
[code]....
MVC 3 razor VB.NET project. I have resorted to manual building a list for a drop down box so I can insure certain values are available in the select list and also to control what the first item is in the list. The below is my code snippet for the part that is giving me problems..
[Code]...
I'm trying to populate class properties where one property is a list collection. I get a NullReferenceException when trying to add to the list collection. The code (litlle bit simplified) is here:
Public Class Portfolio
Property Name As String
Property Assets As List(Of Asset)
Public Sub Populate(ByVal data As DataTable)
For Each row As DataRow In data.Rows
[Code] .....
I have a nested class "Asset" inside the class "Portfolio". Everything goes ok until the line
Me.Assets.Add(asset)
Which gives me the NullReferenceException error.
I get the following error when trying to use this code.If you see that something is wrong with my design then tell me. I want to do this the best I can.Also, I am trying to figure out how to add specific players and coaches to a school. I have coaches and players in separate lists just like the school.
Private Sub populateTable()
For i As Integer = 0 To SchoolList.Count - 1
DataGridView1.Rows.Add(SchoolList.Item(i))
Next
[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 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