How to check the data type in C++

In C++, sometimes we need to check or inspect the type of a variable or expression. So I summarize some ways to implement it.

01 Use typeid

Through using the typeif operator from <typeinfo> to get the type information at runtime.

#include <iostream>
#include <string>
#include <typeinfo>
using namespace std;

int main()
{
   string s;
   cout << typeid(s.c_str()).name() << endl;
}

Output: PKc

PKc is the mangled type used by Itanium C++ ABI(used by GCC/Clang) to represent a specific C++ type.

• P -> Pointer(*)
• K -> const qualifier
• c -> char