Question

After member function delete the current instance，how to stop the behind code executes.
See the code.

#include <iostream>
class A;
void callfun(int i,A *pt);

class A {
public:
    A() { sss="this is A."; }
    virtual ~A() {}
    void foo(int i) {
        callfun(i,this);　　//call a function.Don't return value.Maybe delete instance.
        out();　　　　　　　 
    }
private:
    void out() {
        std::cout<< "Out:" <<std::endl;
        std::cout<< sss << std::endl;
    }
    std::string sss;
}

void callfun(int i,A *pt) {
    if (i==0)
        delete pt;  //If conditions are matched,delete instance.
}

int main() {
    A *a1=new A;
    a1->foo(1);     //print:Out:this is A.
    a1->foo(0);     //delete a1,don't print.But in fact it would print.how to do？
}

I want the result：foo(1) output “Out:this is A.”,foo(0) delete instance,don’t output.

Answer 1

The following is a more complete code.

class A;
class B {
public:
　　void creat() {
        pp=new A;
    }
    void remove() {
        delete pp;
        pp=NULL;
    }
private:
    A *pp;
};

class A {
public:
    void foo(int i) {
        callfun(i,this);　
　　　　if (flag)
            out();　　　　　　
        else 
            bb->remove();
    }
private:
    B *bb;
};