Use of this keyword in C duplicate

Question

In C++, is the keyword this usually omitted? For example:

Person::Person(int age) {
    _age = age;
}

As opposed to:

Person::Person(int age) {
    this->_age = age;
}

Answer 1

Yes, it is optional and generally omitted. 

However, it may be essential for accessing variables after they have been overridden in the scope:

Person::Person() {
    int age;
    this->age = 1;
}

Also, this:

Person::Person(int _age) {
    age = _age;
}

It is pretty bad style; if you need an initializer with the same name use this notation:

Person::Person(int age) : age(age) {}