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Questions tagged [derived-class]

In Object Oriented languages, derived class can inherit properties and/or member functions from a base class, also called super class. cf inheritance and polymorphism.

In Object Oriented languages, derived class can inherit properties and/or member functions from a base class, also called super class. cf inheritance and polymorphism.

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Pointer to array of base class, populate with derived class

If I have a base class, with only virtual methods and 2 derived classes from the base class, with those virtual methods implemented. How do I: // causes C2259 BaseClass* base = new BaseClass[2]; BaseClass[0] = new FirstDerivedClass; …
Deukalion
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static abstract class

I need a way to create a static class where some constants can be case specific, but hard-coded. What I really want to do is have a class where several constants are provided when the class is extended - I want the 'constants' hard-coded. I figured…
David Božjak
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Call derived class method from base class reference

class Material { public: void foo() { cout << "Class Material"; } }; class Unusual_Material : public Material { public: void foo() { cout << "Class Unusual_Material"; } }; int main() { Material strange = Unusual_Material(); …
user487100
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Why does my C++ subclass need an explicit constructor?

I have a base class that declares and defines a constructor, but for some reason my publicly derived class is not seeing that constructor, and I therefore have to explicitly declare a forwarding constructor in the derived class: class WireCount0…
Neil Steiner
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C# "Rename" Property in Derived Class

When you read this you'll be awfully tempted to give advice like "this is a bad idea for the following reason..." Bear with me. I know there are other ways to approach this. This question should be considered trivia. Lets say you have a class…
bopapa_1979
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How could an instance of the base class hold an instance of the derived class?

I have been a .Net coder (can not say I am a programmer) for 2 years. There is one question that I can not understand for years, that is how could an instance of the base class hold an instance of the derived class? Suppose we have two…
NextStep
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Deriving Class from Generic T

I have a parameterized hibernate dao that performs basic crud operations, and when parameterized is used as a delegate to fulfil basic crud operations for a given dao. public class HibernateDao implements GenericDao
bowsie
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Why can’t protected members be used by friends of derived classes?

The C++ standard states in [class.access/1] (emphasis mine): A member of a class can be private; that is, its name can be used only by members and friends of the class in which it is declared. protected; that is, its name can be used only by…
Géry Ogam
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Accessing public static members of a base class specified as private

I'm learning C++. The documentation learn.microsoft.com/en-us/cpp/cpp/member-access-control-cpp says: When you specify a base class as private, it affects only nonstatic members. Public static members are still accessible in the derived…
KarlEL
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c++ casting base class to derived class mess

If I were to create a base class called base and derived classes called derived_1, derived_2 etc... I use a collection of instances of the base class, then when I retrieved an element and tried to use it I would find that C++ thinks it's type is…
alan2here
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Unable to cast Base class (data contract) to derived class

[DataContract] public class SearchCriteria { [DataMember] public string CountryID { get; set; } } [DataContract] public class CitySearchCriteria: SearchCriteria { [DataMember] public string CityID { get; set; } } I am creating…
Nirman
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C# accessing protected member in derived class

I wrote the following code: public class A { protected string Howdy = "Howdy!"; } public class B : A { public void CallHowdy() { A a = new A(); …
Yippie-Ki-Yay
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Serialization of derived objects without the xsi:type

I'm having a problem when serializing a Dictionary containing a list of derived objects. The serialized output contains where I would like the BaseAttributes to be…
dennis_ler
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How to access protected method in base class from derived class?

Here is a sample of code that annoys me: class Base { protected: virtual void foo() = 0; }; class Derived : public Base { private: Base *b; /* Initialized by constructor, not shown here Intended to store a pointer on an…
Bernard Rosset
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Why can't a Base class object be assigned to a Derived class object?

A derived class object can be assigned to a base class object in C++. Derived d; Base b = d; // It's Ok But why can't a base class object be assigned to a derived class object? Base b; Derived d = b; //Not Ok. Compiler give an error Edit: Sorry,…
msc
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