c++ getter not returning value (NULL) - c++

Question

when i try to cout the get function it don't return any value !
my header file :
#pragma once
#include "stdafx.h"
#include <iostream>
#include <string>
using namespace std;
class Dog
{
private:
string dogName = "Max";
public:
Dog();
void talking();
void jumping();
void setDogName(string newDogName);
///////thats the function /////
string getDogName();
};
my cpp file :
#include "stdafx.h"
#include <iostream>
#include <string>
#include "Dog.h"
using namespace std;
Dog::Dog() {
cout << " Dog has been Created " << endl;
}
void Dog::setDogName(string newDogName)
{
newDogName = dogName;
}
string Dog::getDogName()
{
return dogName;
}
and my main.cpp file:
#include "stdafx.h"
#include <iostream>
#include "Dog.h"
#include "Cat.h"
int main()
{
Dog ewila;
ewila.setDogName("3wila");
cout << ewila.getDogName();
return 0;
}
im learning c++ new so i don't know whats happening even i tried to type ewila.getDogName(); by itself and it didn't do anything
and i tried to store the setDogname() in a variable to return with the getDogName() and also nothing i don't know what i'm doing wrong
also : im using visual studio 2017 and i run the program from visual c++ 2015 MSBuild command prompt

Answer 1

The problem is in line newDogName = dogName; of function void Dog::setDogName(string newDogName). You are using assignment operator(=) incorrectly. This should be dogName =newDogName;
So the corrected CPP file will be:
#include "stdafx.h"
#include <iostream>
#include <string>
#include "Dog.h"
using namespace std;
Dog::Dog() {
cout << " Dog has been Created " << endl;
}
void Dog::setDogName(string newDogName)
{
dogName = newDogName;
}
string Dog::getDogName()
{
return dogName;
}