I'm showing a form like this[code]...
Then I am trying to update a progressbar on that form from a public sub in a module, but I don't know how to reference it. I can't use "Me" because I'm not doing the updating in the forms code
I am currently trying to reference a new form that has been created, but I am unsure how I reference a particular instance of the form.
The form that has been created can have up to 4 different instances. Each one is created from the menu. The code that is executed is identical, with a parameter passed 1,2,3,or 4 The form is created with
Dim newScreenDisplay As New ScreenDisplay
and has all the usual text boxes and buttons etc. on it.The display is then kept up to date by refreshing it from variables. This task is performed by a background thread.What I can't work out is how to reference the specific instance of the form that I created as they all have the same name (newScreenDisplay).
I'm having this problem with my code and cannot seem to get past it although it was working fine before. The error is "An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object." The code is:
CODE:
I am trying to get information to be pulled out of a database and show in text boxes on another form (frmviewsdets). The error occurs when it gets to the line frmviewsdets.txtsnumber.Text = rdr("StudentNumber") and even when a breakpoint is applied there it just moves on to the next and so on.
I have tried to show frmviewsdets before I pull the data out of the database beut I get the same message.
I am getting this error "Object reference not set to an instance of an object" and I dont know where/how to fix it and it does not tell me where the error in the code occurs, just a pop-up windows saying the error. Here is the code on the "start up" Windows form..
[Code]...
creating single instance form in MDI Application. How to check whether form's instance created or not?
View 6 RepliesWTF, here's my code...
Public Class Form1
Dim BIT01 As Integer = BIT_01.Text
Dim Value As Integer = TB_OutPut.Text
[code].....
My problem is when i try to call Application.Run() in a application without a form i get "Object reference not set to an instance of an object." when i run it outside VS. but if ran in debug or release mode it works just fine. i may just be forgetting to setup application right, but ive done it before in this same manor and it worked fine.
Sub main() 'this runs first.
AddHandler Application.ApplicationExit, AddressOf ExitEventHandler
dbg_f("handle added")
[CODE]...
Commented out init_timer and init_ready, and now it causes the same error for the myName line. there seems to be something wrong with class Application. btw theres seems to be something wrong with the forum code formatting.
I am using the IndexOf function of the string class to find a specific instance of a string. And based on that I have a logic to do something. Below is the example of what I am doing. The code is in production and is working fine. But for some instance I am getting an "Object reference not set error". Yeah its intermittent.The requestXML is a string of xml data passed in as a paramter to a subroutine. I am fetching the xml string as a form post in a request object. The only thing I could think of getting this kind of error is when the requestXML string varia
requestXml = Request("requestXML")
SubmitRequest(requestXml)
Private
Sub SubmitRequest(ByVal requestXml
[code]....
Dim dir_info As New DirectoryInfo(strDirectory)
dInfo = New DirectoryInfo(strDirectory)
Dim fs_infos() As FileInfo = dir_info.GetFiles("*")
[Code].....
I am trying to create a new ProductID and stored it in a variable intProdID and also to display it on the Label.
But I encounter this error message to my surprise: Object reference not set to an instance of an object
this part of coding generate the error message:Do While DR.Read[code]...
I recently copied a code from internet, which gives me an error of Object Reference Not Set To Instance Of Object, NULL POINTER EXCEPTION. I couldn't understand where the problem lies.[code...]
View 2 RepliesThis was just thrown on me. It operates fine on first load but if I clear the box and click on the button that fires this code I get the NullReferenceException error. Everything is Null or "" on load so basically I am just resetting it
If (Not Trim(txtAssessmentSelectedType.SelectedValue.ToString) Is DBNull.Value And Not Trim(txtAssessmentSelectedType.SelectedValue.ToString) = "") And ((Not Trim(txtAssessmentSelectedTypeLow.Text.ToString) Is DBNull.Value And Not Trim(txtAssessmentSelectedTypeLow.Text.ToString) = "") Or (Not Trim(txtAssessmentSelectedTypeHi.Text.ToString) Is DBNull.Value And Not Trim(txtAssessmentSelectedTypeHi.Text.ToString) = "")) Then
DoAssessment = True
Exit Function
End If
The following code gives me an error: Object reference not set to instance of an object[code]...
View 10 RepliesI have a sub that initiates an instance of a library.object. That instance makes a connection to an instrument. Now I need to close it or change properties/run method from another sub. How do I reference this instance?
Public Class Form1
Private obj As AxCBMCOMMLib.AxCBMComm
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[code]....
This is on my page load. I always encounter Object reference not set to an instance of an object on my ddlStatus drop down list.
HTML
Dim lnkUpdate As LinkButton = FormView1.FindControl("UpdateButton")
Dim ddlStatus As DropDownList = FormView1.FindControl("DropDownList4")
Dim lnkEdit As New LinkButton
Dim lnkDelete As New LinkButton
Dim CurrRow As GridViewRow
[Code] .....
I have Form1 calling Form2 and Form2 calling a sub from anther class on load that populates a combobox.The sub is throwing the exception "Reference not set to an instance of an Object". I do something nearly identical on the main form and it works perfectly.[code]
View 3 RepliesWhen I got a fieldsinfo-array of a class I know all of it's fields. Now, how can I access all of the fields of an instance of the same class by using the fieldsinfo-array? [code]I'm sure there exists a possiblity to get the value of the instance, but how?
View 5 RepliesI am trying to get the bound values from a row in a ListItem. I have a button on each row that when clicked will perform a task (sending an email message to the person who's name and email address is in that listitem row. So, I have an event handler tied to the listview, and I am trying to get to the underlying datarowview to extract the data items.Here's what I have in the event handler:
Protected Sub lvUsers_ItemCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ListViewCommandEventArgs) Handles lvUsers.ItemCommand
Dim diCurrentUser As ListViewDataItem = CType(e.Item, ListViewDataItem)[code]...
Now, it fails at the line where I am trying to access the contact_email element in the DataRowView object.What an I doing wrong?
I've written a new DAL and BLL, but when I try to create an instance of my class, I get an Object Reference error, is there anything particular I should be looking for? I am fairly new to this concept?
Call is such:Protected Sub btnSignin_Click(ByVal sender As Object, ByVal e As System.Web.UI.ImageClickEventArgs) Handles btnSignin.Click Dim l As New Log()l.Log = "Attempted staff login with username [" & txtUsername.Text & "] and password [" & txtPassword.Text & "]"
[Code]...
Intellisense highlights no problems and if I Build the web site in VS I get a few warnings about schema information in the web.config (unrelated), otherwise no problem.
Is it possible using Reflection or some other method to obtain a reference to a specific class instance from the name of that class instance? For example the framework for the applications I develop heavily uses public class instances such as:
Public bMyreference as MyReference = new MyReference
Then throughout the application bMyReference is used by custom controls and code. One of the properties of the custom controls is the "FieldName" which references a Property in these class instances (bMyReference.MyField) as a string. What I would like to be able to do is analyze this string "bMyReference.MyField" and then refer back to the actual Instance/Property.
In VB6 I would use an EVAL or something simular to convert the string to an actual object but this obviously doesn't work in VB.net. What I'm picturing is something like this:
Dim FieldName as String = MyControl.FieldName ' sets FielName to bMyReference.MyField
Dim FieldObject() as String = FieldName.Split(".") ' Split into the Object / Property
Dim myInstance as Object = ......... ' Obtain a reference to the Instance and set as myInstance
Dim myProperty = myInstance.GetType().GetProperty(FieldObject(1))
The code is shown below:-
Function fnt_db_JDE(ByVal connName As String, ByVal strSQL As String) As DataTable
Dim result As New DataTable
Dim dsSysConfig As New DataSet
Dim xmlPath As String = ini("Root") & "SysConfig.xml"
[code]....
The error is with the connStr = '' line.
Whats the best way to instantiate a class so that i can have access to the object from diffreent forms and classes?
View 2 Repliesi got this code from the net , but i can't make this code work on the system i am programming so, i used the same codes to another system and it worked, when i tried using it to my system, it failed, so i started a new program and it still fails... what is wrong with my program? here is a sample of the code:
[code]...
whenever i run the program, it compiles, but when i click the commit button, this message appears "NullReference Exception was unhandled Object reference not set to an instance of an objects" and it points to .NewRow
I have an ssis package that takes a flat file and dumps it to SQL. During that process, 150 columns need to have '-' and '.' removed from them. I have done this using a Script Transformation.
Public Overrides Sub Input0_ProcessInputRow(ByVal Row As Input0Buffer)
Dim column As IDTSInputColumn90
Dim rowType As Type = Row.GetType()
[code]....
Edit I've discovered that this line is the problem
Dim strCol As String = columnValue.GetValue(Row, Nothing).ToString()
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]....
In the Session_Start of the Global.asax i have
Sub Session_Start(ByVal sender As Object, ByVal e As EventArgs)
Session("login") = False
[code]....
Why i am getting error the error Object reference not set to an instance of an object. at line
If Current.Session("login") Is Nothing Then
while checking for the login state as follows?
If GetLogin = False Then
'Do something
End if
I mean i have already created the instance on the Session_Start... Haven't i?
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 am getting this error when I try to print my report. Here is my print code.
Private Sub PrintToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PrintToolStripMenuItem.Click
Dim Print_Dialog As New PrintDialog
[code].....
Here is my error: System.NullReference Exception: Object reference not set to an instance of an object.
[code]
Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click
frmUpdate.Show()
[code]....
with datagridview1
while looping through all the cells
i am trying to allot a cell value to another cell value basing on some conditions
& finally delete one column.my code is as fallows
Dim i, x As Integer
i = 0
x = Me.DataGridView1.Rows.Count[code]....
error i am getting is : Object reference not set to an instance of an object.it is extremely surprising for me the same code has worked nice for me but why & how the same line of code is generating this error.