2 Begginer questions...
Hey, this is my first post and im learning how to program in c++
As i advance in the begginer lessons, 2 questions have been wondering inside my head:
1. How do you use pointers to change, from function A, the value of a variable from another function B? (Or, how do you do it at all :P)
2. How can u return structures from functions? IE:
Being database a predefined struct?
What are the practical uses for this?
1. You make the parameter of the function B a pointer, then pass the address of the variable to the function. In C++, it is usually easier to use references instead. In that case, you would make the parameter of B a reference, and you pass the variable from A normally. Any changes to the parameter in B will affect the variable in A.
2. Your code is correct. There are too many uses for this to list them all or to even start. In C++, a very common design goal is to make structs and classes (which are virtually the same thing) act like built-in types. That means that you pass them to functions or return them from functions just as you would a type like int or double.
Man i get trouble when returning structures from functions...
I get the following error message:
.\Starter.cpp(22) : error C2556: 'main::data fn(void)' : overloaded function differs only by return type from 'char fn(void)'
.\Starter.cpp(6) : see declaration of 'fn'
Basically I define the struct, then create a function with return type of the struct type, but i dont know what to set in the return value of that function...
The error is because you have two functions both named fn, one that returns char and one that returns the struct.
The code should be the same for a struct or an int. Create a variable of the type of your struct and return it. You really need to post the exact code if you have a specific problem.