Remove spaces from std::string in C++

Question

What is the preferred way to remove spaces from a string in C++? I could loop through all the characters and build a new string, but is there a better way?

Answer 1

In C++20 you can use free function std::erase

std::string str = " Hello World  !";
std::erase(str, ' ');

Full example:

#include
#include

int main() {
    std::string str = " Hello World  !";
    std::erase(str, ' ');
    std::cout << "|" << str <<"|";
}

I print | so that it is obvious that space at the begining is also removed.

note: this removes only the space, not every other possible character that may be considered whitespace, see https://en.cppreference.com/w/cpp/string/byte/isspace