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What is the role of the virtual destructor, many novices are not very clear about this, in order to help you solve this problem, the following editor will explain for you in detail, people with this need can come to learn, I hope you can gain something.

If the destructor of a base class is described as a virtual destructor, the destructor in its derived class is also a virtual destructor, regardless of whether it is described with the keyword virtual or not.

The purpose of the virtual destructor is to ensure that the destructor is executed correctly when an object is deleted using the delete operator. Because after setting the virtual destructor, the destructor can be selected by dynamic binding.

Here is an example of using a virtual destructor.

# include

Class A

{

Public:

Virtual ~ A () {cout < < "A Called () Called.\ n";}

}

Class B: public A

{

Public:

B (int I) {buf = new char [I];}

Virtual ~ B ()

{

Delete [] buf

Cout < < "Bazaar Called.\ n"

}

Private:

Char * buf

}

Void fun (A * a)

{

Delete a

}

Void main ()

{

A * a = new B (15)

Fun (a)

}

Execute the program to output the following results:

Called () Borel.

A () Called.

If the destructor in class A does not use a virtual function, the output is as follows:

A () Called.

When it is stated that the destructor of the base class is a virtual function, the fun (a) function is called to execute the following statement:

Delete a

Because the destructor is automatically called when the delete statement is executed, dynamic binding is used to call the destructor of its base class, so the above results are output.

When it is not stated that the destructor of the base class is a virtual function, delete implies a call to the destructor, so it produces

A () Called.

As a result.

Class A {public: virtual ~ A () {cout

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