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what is virtual destructor
- 7 Answers
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Answers were Sorted based on User's Feedback
Answer / isha
Dear friend , you have done a mistake..
Example:
class Employee {
virtual ~Employee() {}
};
class Manager : public Employee {
~Manager() {}
}
Employee * m = new Manager();//here was the mistake
delete m; // <--
| Is This Answer Correct ? | 9 Yes | 0 No |
Answer / kamil mohamed
virtual destructor is recommended when you want to destroy
(delete) an object through it's parent pointer. This good
habit enforces proper cleanup of derived classes
Example:
class Employee {
virtual ~Employee() {}
};
class Manager : public Employee {
~Manager() {}
}
Manager * m = new Employee();
delete m; // <--
| Is This Answer Correct ? | 6 Yes | 1 No |
Answer / rock
When a derived class object pointed to by a base class
pointer dynamically is deleted only the base class
destructor is invoked inorder to even invoke derived class
destructor we use virtual destructor.
class shape
{
virtual ~shape(){}
};
class circle:public shape
{
~circle(){}
};
void main()
{
shape *sh = new circle;
delete sh; //both the destructors are invoked
}
If virtual keyword is not added to the base class
destructor only the base class destructor is called.
| Is This Answer Correct ? | 3 Yes | 0 No |
Answer / pankajkolte
Virtual Destructor is used basically to ensure proper the
sequence of call to destructor.
class Employee {
virtual ~Employee() {}
};
class Manager : public Employee {
~Manager() {}
}
Employee * m = new Manager();//here was the mistake
delete m; // <-
In this case base class destructor if marked as virtual so
as derived class destructor will get called first then base
class destructor.
| Is This Answer Correct ? | 2 Yes | 0 No |
Answer / suresh.k (portblair)
Using virtual destructors, you can destroy objects without
knowing their type - the correct destructor for the object
is invoked using the virtual function mechanism. Note that
destructors can also be declared as pure virtual functions
for abstract classes.
if someone will derive from your class, and if someone will
say "new Derived", where "Derived" is derived from your
class, and if someone will say delete p, where the actual
object's type is "Derived" but the pointer p's type is your
class.
| Is This Answer Correct ? | 2 Yes | 4 No |
Answer / rahul
virtual destructor is just to remove the variable without
knowing its type.....
| Is This Answer Correct ? | 0 Yes | 3 No |
Normally virtual destructor is used to destroy a base class
object without knowing it's type...
| Is This Answer Correct ? | 0 Yes | 3 No |
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