Access Class From Inherited?
Oct 14, 2011I have two classes[code]...
How can I modify class1 in a sub in class2?
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.net - Why Can't Access The Backing Field On An Auto Implemented Property From Within An Inherited Class
Dec 20, 2011I have a class that exposes an auto implemented property Enabled
[Code]...
But If I had not use an auto implemented property and declared my own backing-field as follows this is accessible from the subclass: Private _Enabled as Boolean ---- EDIT ----
The abve line is incorrect - this is not possible, it was in fact Protected in the original code which allowed access from the sub class See @JonSkeet answer ---- EDIT Of course I can just access Enabled from the sub class to work around this but can someone explain why this is the behaviour?
Does An Inherited Class Automatically Implement An Interface From Its Base Class
Jun 10, 2011Suppose I have piece of code like this:
Public Interface ISomething
....
End Interface
[code]....
Returning A Inherited Class As Base Class Type With Web Services?
Sep 25, 2009I suspect I am being very silly here but I have the following setup
Class MustInherit myBaseClass
'some stuff
End Class
Class myInheritedClassA
[code]....
Running this results in the following error
Unhandled Exception: System.InvalidOperationException:
There was an error generating the XML document. --->
System.InvalidOperationException:
[code]....
is there any way of 'Widening' the inherited class to the base class so this would work?
EDIT:regarding XmlInclude(typeof inheritedClass), currently this method could potentially return a number of types of inherited class (i.e myInheritedClassA and myInheritedClassB) is it case of simply having to add each of the inheritedTypes in this tag?
Convert From Base Class To Inherited Class?
Jun 2, 2009I understand that inherited classes can't be converted from base classes. But is there any way to write a conversion sub, so that the base class gets assigned to MyBase, then extra properties are added?[code]...
View 7 RepliesForce An Inherited Class To Use An Attribute On The Class?
Oct 29, 2009I'm trying to force an inherited class to use a custom attribute. I'm creating a class library where the user who wants to create an item will do so, but be forced to add an attribute (or visual studio will automatically add the default attribute) to their inherited class. Here is what I'm hoping to achieve:
BaseClass.vb:
<CustomAttribute(10)> _
Public Class BaseClass
End Class
MyClass.vb:
[Code]...
C# - How To Prevent Class 'a' From Being Inherited By Another Class
Jul 31, 2010i have a class named fdetails and i do not want any other class to inherit from this classCan i set it to not being inherited by another class. I would like to get the things done in the following 3 languages
View 6 RepliesPrevent Class 'a' From Being Inherited By Another Class?
May 23, 2010i have a class named fdetails and i do not want any other class to inherit from this classCan i set it to not being inherited by another class. I would like to get the things done in the following 3 languages
"upgrade" An Object To An Inherited Class, And Keep All The Base Class's Property Values?
Jul 5, 2010bare with me during this silly example. :-) Let's say I have a class like this:
Public Class Animal
Public iLegs as int32 ' Number of legs
Public bWings as Boolean ' Wings? Yes/No
End Class
And another class that inherits the "Animal" class and adds one more property:
Public Class ScaryAnimal
Inherits Animal
Public iScariness as int32 ' 0-100, how scary is it?
End Class
Now, if I have an instance of "Animal" with some values in it, and I decide I want to cast it to a ScaryAnimal for some reason, how do I do that without having to create a new instance of "ScaryAnimal" and copy each property value?Basically I'm looking for a way to do this, without having to write the lines marked with '*** below:
[Code]...
Cast Inherited To Base Class?
May 19, 2010The program below trhows an error in the line "mTable2 = mTable.Copy". The error is: "Unable to cast object of type 'System.Data.DataTable' to type InherintanceQuestion.InheritedTable". This is because mTables is an instance of the InheritedTable class which inherits a DataTable and mTable is a DataTable. So, is there any way I can create the mTable2 to the mTable.copy to the mTable.
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[code].....
Generic Inherited Class Definition
Jan 11, 2010I'm having trouble with the definition of an inherited generic class. I have two base classes that are defined like this:[code]
View 2 RepliesHide A Method In An Inherited Class?
Feb 13, 2010Is there a way to hide a method of a base class that has been inherited?Lets say the base class has the properties:
x
y
Height
Width
and the method
sub SpecialInstructions()
Now this class is inherited by some classes that either use the SpecialInstructions method or override it. But one class inherits it but cant make use of the method and therefore wants to hide it. I tried shadowing but it still seems that the method is visible ex
Private Shadows Sub SpecialInstructions()
Inherited Class Designer Locked ?
Dec 30, 2009I have a class which inherits a form class, and just recently it's started acting strange. All of the controls on the form are locked, and I don't understand why. I can't edit the properties of any controls, or anything.
View 4 RepliesNarrowing The Scope Of Sub In Inherited Class?
Apr 5, 2011Below is example code of what I want to do:
Public Class Test
Sub New()
Dim cool As New B
cool.Doit()
[code]....
Asp.net - Could Not Load Inherited Class For Aspx Page
Feb 29, 2012When I transfer my project to a server, I now get this error message. What does it mean and how do I fix it?
Server Error in '/HD' Application.
Parser Error
Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately.
Parser Error Message: Could not load type 'HD._Default'.
Source Error:
Line 1: <%@ Page Language="vb" AutoEventWireup="false" CodeBehind="Default.aspx.vb" Inherits="HD._Default" %>
Line 2:
[Code]....
Auto-code Generation In Inherited Class?
Jul 10, 2009I am wishing to emulate the auto code generation that happens when you derive from a class, such as Form, and declare the Public Sub New() constructor. When this happens the constructor will auto-generate code like the following:
Public Class MyInheritedForm
Inherits Form
Public Sub New()
[Code].....
Error: Class 'InheritingClass' Has No Accessible 'Sub New' And Cannot Be Inherited
Nov 26, 2010I have an issue with FxCop and the warning: Abstract types should not have constructors.This is being displayed for a number of abstract classes (possibly all, I haven't checked). When I look most of them have no new method so I assume it's the complier adding a default one. So to remove it I add a private default constuctor (Private Sub New()), this then means all the inherting classes fail to build with the error: Class 'InheritingClass' has no accessible 'Sub New' and cannot be inherited.This seems odd as FxCop requests no public constructor, but when I remove it the build fails.
View 1 RepliesInitializing Class Collection Of Inherited Types
Oct 4, 2010Is there a way to have a class collection of inherited types be initialized? For example, here is my code:
Public Class CamryCar
Property Name As String = "Camry"
Property Color As String
End Class
Public Class RedCamry
[Code] .....
I prefer this one as I don't have an extra property to deal with. But I can find a way to initialize that that list with objects of RedCamry and BlueCamry. Is it impossible or is there another way to do this?
Overriding Properties Of A Subclass Of An Inherited Class?
Jun 7, 2012I am trying to override a property of a subclass of an inherited base class. I've tried to simplify this code as much as possible but am not comfortable enough with my own abilities to simplify anything else without loosing the ability to understand an answer.The property propertyName in the otherClass is currently incorrect. I want to be able to override propertyName in baseClass with the propertyName in otherClass. Is this possible to accomplish?
Public Interface interfaceName
Interface iInterfacePropertyName
Enum enumName
[code].....
Set ReadOnly Field In Constructor Of Inherited Class
Apr 1, 2012[Code]...
Is there an explanation for this limitation? I mean, it's still in the constructor for the object, and the base class constructor is still executed first.
Persist A Value In An Inherited Class Or Create A Custom Parameter?
Apr 15, 2012I am making some changes to a fairly old project.It has a DataGrid with an Inherited Class
Public Class CustomDataGridTextBox
Inherits DataGridTextBoxColumn
and a Override Sub Protected Overloads Overrides Sub Paint (.......What it was doing was alternating the Data Grid Line colours New Requirement is to break up some items in the DataGrid By categories So I have added new lines to the data and sorted so they show up ad category headers (Production Stations) And they would like the Category Header to be a different colour and then the alternating line colours to restart.This did not sound too difficult but that has proven a trap Setting the category header is no problem but restarting the alternating colours is Previously the row was determined to be odd or even to set the colour.Now I am intending to use an Integer to define what colour is used but it persists only for that text box.
How can I get it to extend its life so each call can refer to it and update it and set the desired colour?All I need to do is have an integer variable that will hold its value for the next call?
[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]....
Reflection - Function Witch Return Type Is The Class Itself In Inherited Classes?
Dec 10, 2011I have a parent class that is also a factory. For example:
Public Class Factory
Public Function clone() as Factory
' Some logic here
[code].....
VS2008/VB: Moving Subclass VB Code To Inherited Base Class - Where Should Variables/objects Be Declared
Jun 3, 2009In re-engineering a windows forms application, I find that a lot of code-behind in the various form classes is duplicative and I'm trying to centralize as many procedures as possible into a base class which can be inherited and used by the subclassed forms.
This process seems to be going well and is making the code in my subclasses much simpler and hopefully easier to maintain, but I'm not sure where to draw the line between leaving code in the subclasses and engineering for generic resusability and moving it to the base class.
Specifically, in some subclasses I have code which manipulates variables and objects specific to the subclass, and although I could move the code-behind into the base class, the base class code references specific objects which are needed to compile. For example, each subclass manipulates a databound datagridview and form detail controls which allows the user to select between multi-record and detailed single-record views of a datatable.
In Visual Basic 2008 do I need to declare dummy data objects in the base class so that the base class will compile? Or is there a way to indicate that the data objects will be provided by the subclass?
Base Form And Inherited Other Forms From It - Don't See Those Changes Take Effect In My Inherited Forms?
Jun 24, 2010I have a base form and I inherit other forms from it. However, if i go back and change say the size of the base form, I don't see those changes take effect in my inherited forms. Does anyone know why that is? Is there a solution to this issue?So as far as design is goes, what exactly gets inherited by other forms?
View 9 RepliesRedeclaring Something In An Inherited Class Is The Recommended-preferred Way To Use "SHADOWS" Or "OVERLOADS"?
Aug 7, 2011PASTE ALL of this to your Form1 code window please and add one Button to Form1.
Now I am asking developers here who actually do software development for a living
especially those persons holding MCPD or similar Microsoft Certification please.
1) When redeclaring a method as in AnotherClass below which Inherits from ExampleClass,
is the recommnded way to use SHADOWS or OVERLOADS please? 2) What about when you do the same with a PROPERTY please?
Option Strict On
Option Explicit On
Option Infer Off
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[Code]...
Access To Object Passed ByRef In The Constructor Of A Class Through Another Part Of The Class?
Aug 18, 2009I have some classes, BsfciFile and StudyFlashCard. Bsfci is the extension to which I save my set of flashcards in an INI format. I am currently working to transform my code from using Windows API calls to access the INI to using a IniFile class that I found on the internet. I would like the BsfciFile to have a Array of StudyFlashCard objects, but I would like the StudyFlashCard class to use the IniFile class object contained in the BsfciFile class. I can pass the IniFile from the BsfciFile class to the constructor for the StudyFlashCard class, but I want it to modify the same IniFile as the BsfciFile class has later on.
[Code]...
Access Members Of A Sub Class Through A Property Of The Parent Class?
Mar 30, 2010This is a bit of a continuation from a previous post for which AtmaWeapon was very informative.
Problem:
A parent class has a sub class with various properties. A property of the parent class is a List(of T) with T = the sub class The issue is how to store data in the sub class of the instantiated parent
Some example code (hopefully formatted correctly):
Code:
'=========== Class Definitions =============
Public Class courseClass
Public Class timeTableClass
[Code].....
Access The Base Class Inside A Derived Class?
Oct 22, 2010How do I access the base class inside a derived class?
View 1 RepliesCan't Access Class From Code-behind. Class Is App_Code Folder?
Feb 15, 2011I have a very simple class that is located within my App_Code folder in my VS2008 web application project. I am trying to instantiate an instance of this class from my code-behind file. Intellisense does not seem to be seeing my class and I am not sure why. I am using VB.NET which I am admittedly not that familiar with as compared to C#. Perhaps I am missing something. I would bet it has something to do with something I am missing in VB.NET.Here is my simple class (for testing):
[Code]...