VS 2008 Reference The Same Instance Of A Class From Different Classes?
Feb 2, 2010Whats the best way to instantiate a class so that i can have access to the object from diffreent forms and classes?
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Object Reference Not Set To An Instance Of An Object With A Class With An Array Of Classes As A Member?
Aug 6, 2010Here is the structure that I have:
Friend Class StandardFormatFile
Friend fileType As String
Friend numberOfSeries As Integer
[code].....
Instance A Class, Based On Other Classes, Add New Properties?
May 26, 2009You know how everyone says "C++ is like C with classes"?How similar is it to .NET classes? instance a class, based on other classes, add new properties, override existing properties, etc?Are the variables strongly-typed and declared before they are used? Or is it a Duck-Typing language like Python?
Also, does it have its own Garbage Collector that disposes of objects when the pointer exits their scope,or do you have to manually clear and get rid of them when you finish with them? What's the difference between native C++, and the "managed C++" in Visual Studio? Because I'd prefer to use native code if its not too much harder. for the sake of all that is good and holy, don't use ACCESS, EXCEL, or a TEXT FILE as a database. If you want your program to use a "local database", without any of the hassle of setting up a MS SQL or MySQL server, just click this link: >>> SQLite <<< Seriously. This is for your own good.
How To Assign A Different Reference To A Class Instance From Inside The Class Code
Jan 18, 2011my proble is the following: I have a class MyClass and another class Modifier, which has a method ModifyMyClass(ByRef mc as MyClass) that receives a MyClass instance as ByRef parameter to modify it. A smell of the code is:
[Code]...
Class With Class Properties: AObject Reference Not Set To An Instance?
Aug 19, 2009I have a class in which some of the fields are also classes.I can put values in the "normal" properties, but in the others when o try to assign values it gives the: "Object reference not set to an instance of an object"But the code compiles fine.
dados_Defenicao = New ServiceReference1.draftClaimEntryDefinition
dados_Defenicao.arCode = "123"
dados_Defenicao.claimMarket.warrantyType = "w" - Here it gives the error
How can i fix this ?
Class With Class Properties: Object Reference Not Set To An Instance
Aug 19, 2009I have a class in which some of the fields are also classes.
I can put values in the "normal" properties, but in the others when o try to assign values it gives the: "Object reference not set to an instance of an object"
But the code compiles fine.
dados_Defenicao = New ServiceReference1.draftClaimEntryDefinition
dados_Defenicao.arCode = "123"
dados_Defenicao.claimMarket.warrantyType = "w" - Here it gives the error
Get A Reference To The Class That Creates An Instance Of Another Class?
May 20, 2010I need to create a new instance of a class that needs a member of the calling class. But i can't pass a reference to the calling class through the constructor.The solution i am looking for is something like this:
Public Class ChildClass
Public Sub New(args)
_MyMember = GetMemberFromCallingClass()
[code]....
I want this to work without having to manually pass any references or variables from the calling class to the new instance of ChildClass.
Obtaining Reference To Class Instance By String Name?
Mar 12, 2010Is 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))
[2008] Reference An Instance From Another Sub?
Jan 11, 2009I 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]....
VS 2008 Reference Parent Class From Inside Child Class?
Apr 11, 2009I have a 'property management class' that contains several functions and properties. I have several other classes that use the 'management class' as a property to derive the value of several of its other properties.Is there a way for me to reference the outer class from the 'management class' functions without having to pass it as a parameter? I ask because several different classes can have this 'management class' as a property and am having a hard time typing the parameter.
View 7 RepliesVS 2010 Structure Classes So That The User Interfaces Though A Single Class While The Supporting Classes Are Hidden From Their View?
Jun 13, 2012How can I structure my classes so that the user interfaces though a single class while the supporting classes are hidden from their view? I think its best understood in an example:
Public Class MyInterface
Public Economic as EconomicClass
Public Sub New()
MyBase.New()
[code].....
So you might ask why am I even separating them? It's strictly for others who will be working with this interface. I need to funnel them though a logical structure:
interface.Economic.MyMethod
interface.Currency.MyMethod
etc
This way everything is already handled for them in the background and they only need to run the method they need. I don't know if I can have it both ways in VB.NET.
[2008] Base Class Inherited By 2 Derived Classes
Jan 30, 2009i've finally got round to learning about classes and inheritance, but i'm not sure how to proceed. i have a base class Employee, which is inherited by 2 derived classes. how do i use the same Employee class in both derived classes? obviously if i write a sub new for both of them + declare a new Employee class, they won't be using the same class. heres my Employee class:
[Code]....
VS 2008 Define A Class As An Instance?
Apr 17, 2010I would like to define a class as something like a constant, and use the class directly rather than having to always create an instance. Is this possible? I've tried a handful of combinations of syntax, but nothing I've tried lets me do what I'm after. To give an idea of what I'm after:
[Code]...
VS 2008 New Instance Of A Class With An Unknown Name
Apr 25, 2012is it possible to declare a new instance of a class using a name contained in another varible which is unknown?
For Instance....
Dim Clients() As String
Then say two clients are connected that array may contain the following:
Clients(0) = Client1245
Clients(1) = Client4856
I now need to create an instance of my class 'clsClient' for each client connecting so my thought was to declare it using the clients unique name/number. I know this isnt valid code but as an example
Dim clients(0) as New clsClient
So I would then have an instance of clsClient called Client1245 and if I had a routine in clsclient called for instance StartClient() i could then do
Client1245.StartClient()
Yes I know the code isnt valid but I think it gets across what I am trying to do and hopefully one of you smartass's will be able to instruct me on what I am trying to do and hopefully not too complex :-)
VS 2008 When To Create A New Class Instance
Jun 22, 2010I understand if i was to create my own class i would need to declare a variable with the new keyword to create an object to access the encapsulated methods properties etc, unless they were declared shared.
dim myVar as myClass = new myClass
But in this next example is where i have become confused. i have added the mschart control to the form and used the hittest function with the following code.
Dim myVar as hittestresult
myvar = me.chart1.hittest(e.x,e.y)
Why wasn't it necessary to create a new instance of the class 1st. Does the hittest function return an object or a reference pointer to the object. To clarify what's the protocol for when & when not to create a new instance of the class in use.
2008 Debugging - Form That Creates An Instance Of A New Class
Dec 8, 2009I have a form that creates an instance of a New Class. The code is simple so there is no issues with the programming.
I can step through the code on the Main Form without issues. Stepping Into moves from 1 line to the next.
I can't seem to debug the code within the class though. I set breakpoints but "stepping into" doesn't work. The code gets executed, but it doesn't step through each instruction.
I've tried changing many of the options within Tools > Debug with no luck.
I've tried deleting files from bindebug and obdebug.
Not being able to debug my programs.
Calling An Instance Of Nested Classes
Jul 14, 2011I`m a beginner in programming and i`m having problems calling an instance of my nested classes. I`m using VB.net and my code is something like this
[Code]....
Create A New Instance Of The Windows Media Player Class In VB 2008 Code?
Dec 13, 2009I do not want a Windows Media Player control on my form. I am making an alarm clock. I have tried this: Friend WithEvents WindowsMediaPlayer As New Microsoft.Win32. But I do not see a Windows Media Player member. I also asked on the MSDN VB Forum.
View 1 RepliesGet A Value Inside Parent Class From Child Class (in Nested Classes)?
Jan 1, 2012I have Class1 and class2 which is inside class1, VB.NET code:
Public Class class1
Public varisbleX As Integer = 1
Public Class class2
[code]....
Working With An Instance Of A Dataset / Datatable From Other Classes
Apr 27, 2010vs2010 vb.net QUESTION1 If i do a select and fill a datatable and want to access that data from another class. How can I do that? QUESTION1 example
[Code]...
VS 2008 Reference The DLL By Navigating To Class Project?
Jan 11, 2010I created a class library of useful functions and it compiled successfully into a DLL. It works great but I need to reference the DLL by navigating to my class project.
Can't I just move the DLL into the System32 folder and point to that reference? Do I need to register it with the OS or can I simply drag & drop?
VS 2008 - Error With Arraylist In My.Settings - Object Reference Not Set To An Instance Of An Object
Mar 14, 2010The issue is when I try to add a new item to the ArrayList with the following code, it gives me an error:
vb Private Sub btnLabelAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLabelAdd.Click
Dim result As String = InputBox("New Filter Label:", "Label List")
[CODE]................
Object reference not set to an instance of an object.
I'm not really sure what I'm supposed to be doing with this. It's a new setting I just added and it's empty, so I'm not sure if that has anything to do with it or not. Anyone know what's going on and what needs to be done to get it to accept a value and not want to be "initialized"?
VS 2008 Error - System.NullReferenceException: Object Reference Not Sent To An Instance Of An Object
Oct 23, 2009I 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).
VS 2008 FindControl - Error : Object Reference Not Set To An Instance Of An Object
Sep 15, 2010What is the problem in below code.
d Public Sub filltextbox(ByVal dlist As String) Dim tb As TextBox = CType(Page.FindControl(dlist), TextBox) tb.Text = "hello" End Sub
Error : Object reference not set to an instance of an object.
VS 2008 System.NullReferenceException: Object Reference Not Set To An Instance Of An Object?
Apr 26, 2011look after the error i'm having.
module1.vb
Imports System.Data.SqlClient
Module dbconn
[code]....
VS 2008 Class Library - Declare New Instance Of MainClass() Before Using Subs/Functions In Class2 Or Class3?
Feb 3, 2011Namespace MyClassLib
Public Class MainClass
Public Sub New()
[CODE]...
Is it possible to make it so that the user using the Class Library has to declare a new Instance of MainClass() before using Subs/Functions in Class2 or Class3?
VS 2008 : Error - Object Reference Not Set To An Instance Of An Object
Dec 5, 2010I create one function to run any select query. and return the OdbcDataReader type.But some time if there is no data it through error : Object reference not set to an instance of an object I need to know how i can control if there is no data.
Public Function Select_From_AnyTable(ByVal sqls As String, ByVal ConStr As String) Dim conn As OdbcConnection conn = New OdbcConnection(ConStr) Dim cmd As OdbcCommand = conn.CreateCommand() conn.Open() cmd.CommandText = sqls Dim reader As OdbcDataReader = cmd.ExecuteReader While reader.Read() Return reader End While conn.Close() End Function Dim ei As OdbcDataReader = Select_From_AnyTable("SELECT loginname from usertable limit 1", conStr) msgbox(ei.item("loginname "))
If there is data it work well but if no record found it through the error.
VS 2008 Error : Object Reference Not Set To An Instance Of An Object
Mar 21, 2010Like every other program that you make when you code a button to open the next form it should open right. Well not in my case. I don't understand the problem that Visual Basics is not seeing my next form that I'm trying to open. When its in the Solution Explorer plain as day. Error below.An error occurred creating the form. See Exception.InnerException for details. The error is: Object reference not set to an instance of an object.show is not set to a object. All its doing is opening the next form. Ive use this code over an over. Now its giving me this C.O.S. error.
View 27 RepliesVS 2008 Error: Object Reference Not Set To An Instance Of An Object
Nov 16, 2010Basically all I am trying to do is to insert data entered in a text box(description) on the application form into database(sql2008) in vb.net. The vb code I wrote is below:
vb.net
Protected Sub Save_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Save.Click
Dim note As String = Description.Text
[code]....
However when I click on save button, I get following message:
System.NullReferenceException: Object reference not set to an instance of an object.
VS 2008 Error: Object Reference Not Set To An Instance Of An Object?
Nov 30, 2010What in this code might be causing this??This part of the code is Hilighted as causing the error.
My.Settings.Item(Holiday_" & i) = DirectCast(Me.Controls("ComboBox" & i.ToString), ComboBox).SelectedItem
Public Sub btn_Update_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
[code].....