The 2 types of C++ Class Methods: Inside Class Definition and Outside Class Definition

Inside Class Definition

class MyClass {        // The class
  public:              // Access specifier
    void myMethod() {  // Method/function defined inside the class
      cout << "Hello World!";
    }
};

int main() {
  MyClass myObj;     // Create an object of MyClass
  myObj.myMethod();  // Call the method
  return 0;
}

In the following example, we define a function inside the class, and we name it “myMethod".

You access methods just like you access attributes; by creating an object of the class and using the dot syntax (.)

Functions defined inside the class are treated as inline functions automatically if the function definition doesn’t contain looping statements or complex multiple line operations.

Outside Class Definition

class MyClass {        // The class
  public:              // Access specifier
    void myMethod();   // Method/function declaration
};

// Method/function definition outside the class
void MyClass::myMethod() {
  cout << "Hello World!";
}

int main() {
  MyClass myObj;     // Create an object of MyClass
  myObj.myMethod();  // Call the method
  return 0;
}

To define a function outside the class definition, you have to declare it inside the class and then define it outside of the class. This is done by specifiying the name of the class, followed the scope…