derived-class

i have a base class A and a derived class B which are stored in the following folder structures. +myPackage (package Path) @A ( folder of class A ) A.m ( filename of class ) @B B.m Now i want to use class B which has the following head classdef B < A unfortunately this does not work because they are in different folders and i cannot import like this: import myPackage.* classdef B < A Is it possible to solve this without loosing the folder organisation? I think if you write classdef B < mypackage.A it should work. 来源： https://stackoverflow.com/questions/8475312/matlab-import-package-for-base

let's say I have a pointer to some base class and I want to create a new instance of this object's derived class. How can I do this? class Base { // virtual }; class Derived : Base { // ... }; void someFunction(Base *b) { Base *newInstance = new Derived(); // but here I don't know how I can get the Derived class type from *b } void test() { Derived *d = new Derived(); someFunction(d); } Cloning struct Base { virtual Base* clone() { return new Base(*this); } }; struct Derived : Base { virtual Base* clone() { return new Derived(*this); } }; void someFunction(Base* b) { Base* newInstance = b-

I would like to write a static instance property in a base class and derive this, but I am facing some problems. Here is the code for the base class - I currently have: public abstract class ResourceInstance<T> { private static T _instance; public static T Instance { get { if (_instance != null) return _instance; var method = MethodBase.GetCurrentMethod(); var declaringType = method.DeclaringType; if (declaringType != null) { var name = declaringType.Name; _instance = (T)Application.Current.TryFindResource(name); } return _instance; } } } As you can see its primary use is for WPF Resources

Suppose I have an abstract base class Deck: public abstract class Deck { public List<Card> cards; public Deck(string[] values, string[] suits) {...} ... } and a derived class EuchreDeck: public class EuchreDeck : Deck { string[] values = new string[] { "9", "10", "J", "Q", "K", "A" }; string[] suits = new string[] { "clubs", "spades", "hearts", "diamonds" }; public EuchreDeck() : base(values, suits) // Error. {} ... } I want the ability to instantiate EuchreDeck and have the two string arrays passed to the base class, i.e. var gameDeck = new EuchreDeck(); . Currently I'm getting the error: "An

I have tried for hours to code a class deriving from boost::variant . But I do not understand what is the problem (I do not understand what the compilation error means). What are the rules to implement a clean boost::variant derived-class? #include <boost/variant.hpp> class MyVariant : public boost::variant<char,bool> { public: MyVariant () : boost::variant<char,bool>( ) {} template <typename T> MyVariant( T& v) : boost::variant<char,bool>(v) {} template <typename T> MyVariant(const T& v) : boost::variant<char,bool>(v) {} }; int main () { MyVariant a; MyVariant b = a; //compilation error //

public class SuperCar: Car { public bool SuperWheels { get {return true; } } } public class Car { public bool HasSteeringWheel { get {return true;} } } How can I set the base class for the derived Supercar? For example, I want to simply set SuperCars base class like this: public void SetCar( Car car ) { SuperCar scar = new SuperCar(); car.Base = car; } Basically, if I have Car objects, I do not want to manually iterate through every property of the car in order to setup the SuperCar oject, which I think is the only way you can do it but if you can do it the other way it would be sooo much

I need to create a number of classes (more than 50) from a base class, where the only difference is in the names of the derived classes. For example, my base class is defined as: class BaseError : public std::exception { private: int osErrorCode; const std::string errorMsg; public: int ec; BaseError () : std::exception(), errorMsg() {} BaseError (int errorCode, int osErrCode, const std::string& msg) : std::exception(), errorMsg(msg) { ec = errorCode; osErrorCode = osErrCode; } BaseError (const BaseError& other) : std::exception(other), errorMsg(other.errorMsg) { ec = other.errorCode;

My base class: //Element.h class Element { public: Element(); virtual ~Element(){}; // not sure if I need this virtual Element& plus(const Element&); virtual Element& minus(const Element&); }; Derived template class: //Vector.h #include "Element.h" template <class T> class Vector: public Element { T x, y, z; public: //constructors Vector(); Vector(const T& x, const T& y = 0, const T& z =0); Vector(const Vector& u); ... //operations Element& plus(const Element&) const; Element& minus(const Element&) const; ... }; ... //summation template <class T> Element& Vector<T>::plus(const Element& v)

I believe Constructors and Destructors in base class cannot be inherited by derived classes of the base class. Is my understanding correct. Your understanding is correct. For example, if you have class Base { Base(int i) {} }; class Derived: public Base {}; Derived d(3); This will not compile because the Base constructor is not inherited. Note that default and copy constructor are created by the compiler if possible, and call the corresponding constructor of base classes, therefore for those constructors it looks as if those were inherited. Niels I think this is what you are looking for? You