I don't understand the point of pointers to classes [duplicate]
Digital Marketing
Facebook Marketing API
.
2 years ago
0
0
0
0
+10 pts
5 Star Rating
5 Rating
_x000D_
_x000D_
_x000D_
This question already has an answer here:_x000D_
_x000D_
_x000D_
Why should I use a pointer rather than the object itself?_x000D_
_x000D_
21 answers_x000D_
_x000D_
_x000D_
_x000D_
_x000D_
I was reading through C++ tutorial and came across this example code.
// pointer to classes example
#include
using namespace std;
class Rectangle {
int width, height;
public:
Rectangle(int x, int y) : width(x), height(y) {}
int area(void) { return width * height; }
};
int main() {
Rectangle obj (3, 4);
Rectangle * foo, * bar, * baz;
foo = &obj;
bar = new Rectangle (5, 6);
baz = new Rectangle[2] { {2,5}, {3,6} };
cout << "obj's area: " << obj.area() << '\n';
cout << "*foo's area: " << foo->area() << '\n';
cout << "*bar's area: " << bar->area() << '\n';
cout << "baz[0]'s area:" << baz[0].area() << '\n';
cout << "baz[1]'s area:" << baz[1].area() << '\n';
delete bar;
delete[] baz;
return 0;
}
So the address of obj (&obj) is assigned to foo, then by using foo->area(), one can calculate foo's area. But why go through all that trouble? What benefit does foo pointer offer? Because to me, it seems like simply instantiating foo just by Rectangle foo and using foo.area() to calculate the area is easier. But when would you use Rectangle *foo and the address to do the same thing?
Posted on 16 Aug 2022, this text provides information on Facebook Marketing API related to Digital Marketing. Please note that while accuracy is prioritized, the data presented might not be entirely correct or up-to-date. This information is offered for general knowledge and informational purposes only, and should not be considered as a substitute for professional advice.
Take Quiz To Earn Credits!
Turn Your Knowledge into Earnings.