How to call a method without first calling it's constructor in C#

wish help you to fix your issue From the JLS, § 8.8.7:

To fix this issue Are you looking to do DNI = generaDNI(); in the constructor? You can just add that line, e.g.:

Persona(){
    nombre = "";
    DNI = generaDNI();
    sexo = 'M';
    // you don't need to set edad, altura, or peso - they default to 0
}

I hope this helps you . I have a C++ code that seems to be confusing a class contructor like A::A(B b) with a constructor that receives a function pointer, like A::A(B (*)()). Let me explain: , It's a veiled most vexing parse issue:

Container c3(Item());

Container c3{Item()};

Does that help A constructor is not like other functions in C++. A constructor's job is to initialize an object. In order to ensure the object gets initialized in a sensible way, all of the member objects (and base objects) need to be initialized. *This happens before the opening brace of the constructor body, so that everything is in a sensible state when you're in the constructor body.
To make sure this happens in the way you want, you can use an initializer list (note that this term also refers to something else when initializing various containers; if you've heard the term before in relation to that, it's not what I'm discussing here). After the function signature, you put a colon, followed by each member of your class (in the same order they're declared in the class) and how you want to initialize it. For example, if you have the following struct

struct A {
    int i;
    char c;
    std::string s;
    A();
};

A::A() : i{17}, c{'q'}, s{"Hello, mrb! Welcome to Stack Overflow"}
{
    // Nothing to do in the body of the constructor
}