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]....
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Loop And Enumerate Properties Of Nested Classes In Nested Classes?
Sep 24, 2010so far i got
code
For Each item As Reflection.FieldInfo In GetType(NameSpace.ClassWithNestedClasses).GetFields
rtfAppend(item.Name & ":" & Tab & item.GetValue(Me))
Next
For Each item As Reflection.PropertyInfo In GetType(NameSpace.ClassWithNestedClasses).GetProperties()
[code]...
which gets me the simple string vars and properties of my top class, but how can i apply this to loop through all sub classes and get there vars and props?
Use LINQ To Filter Collection Of Nested Classes To Yield Dictionary Of Unique Properties Of Those Classes?
Jan 23, 2012I have two classes, one nested in the other. [code]Neither "Name" or "ID" are unique between operations and records.I wish to construct a dictionary using LINQ = Dictionary(Of String, Of List(Of Integer), whereby the keys are uniqe examples of Names in my collection and the values are the collective set of distinct IDs that are associated with those names.
View 2 RepliesVS 2010 Calling Subs And Functions Within Classes That Are Within Classes?
Oct 24, 2009Here is some example code of what I mean:
vb
Public Class Form1
Private Sub Button1_Click(ByVal sender as Object, e as systemEventArgs) Handles Button1.Click
[Code]....
VS 2010 Nested Classes
Oct 16, 2011I've seen people discourage other from using nested classes, because the make things more complicated and are evil and whatnot.But I want to know what possible justification there would be for using a nested class and if there are any possible benefits for using them(or structures for that matter).
View 10 RepliesVS 2010 Variable Scope In Nested Classes?
Jul 13, 2011I have put together the following code to illustrate the problems I've been struggling with:
Public Class OuterClass
Private _OuterProp1 As Boolean = False
Public Property OuterProp1 As Boolean
[code]....
I need to be able to refer to outer class properties and variables in an inner class, and I need to have a variable in one inner class set in a different class. I've tried Public, Private, Protected, Friend and all kinds of combinations of them, and I can't figure it out.
Calling Sub From Other Classes - No Value?
Oct 28, 2009created class TestA. There is Sub mysub defined inside it. Now I want to use this Sub in other class. So far I did like this:
Dim oTestA As New TestA
Dim dblA As Double
dblA = oTestA.mysub
[code].....
Calling The Classes To Be Used In The Main Form?
Apr 3, 2012I have an original assignment that works fine, now I need to go back and make it into classes. I am not 100% how to do this. My issues are with calling the classes to be used in the main form, and what to put into the classes.
I will post the original working assignment and my understanding of the classes.
[Code]...
Get 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]....
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.
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?
View 2 RepliesWorking 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
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Startup Next Instance - Calling Sub?
Aug 8, 2009Basically I have a single instance project, when a user right clicks an image it trys to host it. I use this code.
Code:
Private Sub MyApplication_StartupNextInstance(ByVal sender As Object, _
ByVal e As StartupNextInstanceEventArgs) _
Handles Me.StartupNextInstance
e.BringToForeground = True
MainForm.Visible = True
[Code] .....
The msgbox is only there to show me I caught the arg. My question is how can I use this info in my application? Every google link is red. I need to add the DIR varible to txtFilePath.Text and then call my sub Call UploadPicture()
Throw System.Exceptions From Within Custom Classes To Calling Code
Jul 9, 2010I Have just been watching a video on throwing Exceptions. Are you supposed to throw System.Exceptions from within your custom classes. to the calling code, Which other way can they communicate. I have read in several places it is bad practice to throw SystemExeptions.
View 3 RepliesUnable To Use An Instance Of The Nested Class Through A Public Variable Of The Parent Class?
Jun 7, 2012I want to created a nested class that can only be visible to and instantiated from the parent class.But I also want to be able to use an instance of the nested class through a public variable of the parent class.I tried making the nested class private, or making the nested class' constructor private, but it won't compile.Is it possible to do this in .NET?
[Code]...
Asp.net - Nested Repeater Error: Object Reference Not Set To An Instance Of An Object?
Jul 28, 2011I am taking some code that I have used for a nested listview before and trying to make it work with a nested Repeater but I am getting an error.
System.NullReferenceException: Object reference not set to an instance of an object.
.aspx
<asp:Repeater ID="reMainNav" runat="server">
<HeaderTemplate><ul></HeaderTemplate>[code].....
Nested Tabcontrol - Error - Object Reference Not Set To An Instance Of An Object
Apr 7, 2011I am using VS2008 and vb.net.I have a nested tabcontrol.
tabControl 1 and tabControl3
In tabControl3 I am trying to populate a text control with a value from a control placed on tabControl1.
' add a savings tabpage
Dim strSavingsPage As String
Dim dblTaxRate As Double
[code]....
The complete error is: NullReference exception was unhandled Object reference not set to an instance of an object.
.net - Prohibit An Instance From Calling Shared/Static Method?
Aug 27, 2010Is it possible to prohibit an instance of a class from calling a shared/static method?
For example:
I want to allow this:
ClassName.MethodOne()
But I want to disallow this:
Dim A As New ClassName
A.MethodOne()
The reason this is desirable is that in this case it is semantically confusing if an instance can call the method.
Can't Create New Instance Of Form After Calling MyForm.close()?
Mar 9, 2009[Edit] See this post as to why I'm declaring form elements globally. I chose to rewire my code to get rid of the global definitions. [End Edit] I'm creating a from dynamically at runtime. the form, all buttons, and the combobox are all declared globally to the parent form. dim myForm as new form
[Code]...
Access Of Shared Member, Constant Member, Enum Memberor Nested Type Through An Instance; Qualifying Expression Will Not Be Evaluated?
Jun 23, 2009i changed a class variable to shared so i can access it in all instances of the class, but it caused an error. what is causing this, and how can i fix it?
Private
Shared img As Bitmap
Me
.img = bgImage
Use Keyword To Create Object Instance & Check If It Is Null Before Calling Method
Sep 26, 2010Use the "new" keyword to create an object instance & Check to determine if the object is null before calling the method. I'm reading text from a text file using the following [Code]
View 9 RepliesAccess Of Shared Member, Constant Member, Enum Member Or Nested Type Through An Instance; Qualifying Expression Will Not Be Evaluated
Jun 2, 2011how do I overcome it? I have created a class and compiled into .dll This code
[Code]...
Warning 1: Access Of Shared Member, Constant Member, Enum Member Or Nested Type Through An Instance; Qualifying Expression Will Not Be Evaluated
May 31, 2010In the following code i get a warning at line 59:Warning 1: Access of shared member, constant member, enum member or nested type through an instance; qualifying expression will not be evaluated.and.. At line 78 I get this Warning:
Warning 2 Property 'SelectedCustomer' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used.
The program compiles and runs well, but i cant' undesrtand the reason for these warnings. Any Idea ?
1: Public Class Form1
2:
3: 'Form level members
4: Private objCustomers As New ArrayList
[code]....
Array Of Child Objects In Nested Classes And Accessing Child Objects In .Net
Jan 3, 2012I have a nested class, let's call it class1 and it has class2 inside it; VB.Net eg:[code]
1) How can I define X number of Class2 objects[let's call it: Node(x) array]** with NEW() subroutine called?' this raises error: dim cls2(n) as new class2 end sub.
2) How can I return actual number of Node() array? [code]Outside my class in main project I define cls1 object:[code]Now an array of class2 is created inside cls1.
3) Now,How can I access All of them[node(x) array which is created inside cls1] with all properties and methods available?
I remember I wrote a ProcessManager class with this functionality in .net 2003, nearly 4 years age, I don't have the code now.
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].....
Forms :: Getting Error "reference Not Set To An Instance" When Calling A Sub?
Jul 16, 2009The first sub calls LoadRaceTimer without a problem. The second results in a "object reference not set to an instance of an object" error. I can't for the life of me figure out why. All three are in "Public Class MainScreen".
Private Sub SessionsBrowser_DocumentCompleted(ByVal sender As System.Object, ByVal e As System.Windows.Forms.WebBrowserDocumentCompletedEventArgs) Handles SessionsBrowser.DocumentCompleted
...
LoadRaceTimer()
[code]....
Object Reference Not Set To An Instance Of An Object When Calling A Function
Jun 13, 2012I call the function GetDataTable and when it gets to the return line, I get the error message: Object reference not set to an instance of an object.
Dim DB As New DBConn
Dim gd As New DataAccess.GetData
Dim DT As New DataTable
[Code].....
Updated. I'll see if I can update with the DataAccess.GetData code. I didn't originally put it in there because our shop use it all the time and have no issues with it.
VS 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.
Derived Classes Cannot Raise Base Classes
Jul 10, 2009I m trying to raise Click event of Textbox explictly but I m getting "Derived classes cannot raise base classes" error.[code]....
View 1 Replies.net - Save System.Collections.Specialized.NameValueCollection Instance To Hard Disk And Load It Back As An Instance?
Jun 24, 2011I have following instance of System.Collections.Specialized.NameValueCollection:
Dim UserSelection As New System.Collections.Specialized.NameValueCollection
UserSelection.Add("D_Color1", "Black")
UserSelection.Add("D_Color2", "Green")
UserSelection.Add("D_Color3", "Purple")
I need to save this instance to hard disk and then load it back from hard disk as an instance. How do I do that?