- class A
-
{
-
.....
-
void getdata(int x, int y)
-
{
-
..........
-
}
-
.....
-
.....
-
}
-
main()
-
{
-
A a1.getdata(10,20), a2.getdata(20,40);
-
.....
-
}
2 1840 Banfa 9,065
Recognized Expert Moderator Expert
The only way to create an object without calling a constructor for it would be to allocate an array of memory large enough and then point a pointer to the object at the array, however that is extremely in advisable. -
char *buffer = reinterpret_cast<char *>(malloc(sizeof A));
-
A* pa = reinterpret_cast<A *>(buffer);
-
Even this, due to object alignment may not work without further fiddling to ensure the object alignment was correct.
This syntax
is not valid and even if it were valid it would call the default constructor of A first. The closest you could get to this syntax is -
class A
-
{
-
public:
-
A& getdata(int, int)
-
{
-
return *this;
-
}
-
-
};
-
-
int main()
-
{
-
A a = A().getdata(0, 1);
-
-
return 0;
-
}
-
which calls both the default and copy constructors of A
Constructors do not create objects.
Only the compiler can create objects. Either on its own or by your command.
After the compiler allocates the memory, the constructors for each data member are called to initialize the memory.
In this example. it's odd that A::getdata does not get the data since the return is void.
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