How to use string as type in header file in C++

Question

I wanna use string as a type in my class header file, but even with and without the string lib, it shows me:
error: 'string' does not name a type
How can I use string in the header?

Answer 1

std::string string_name;

Answer 2

#include <string>

Answer 3

It doesn't work

Answer 4

OOOOHHHHH, it's true 🇮🇳Omkar🕉 ! I forgot that the namespace STD wasn't used as default.

Answer 5

#include <cstring>