是否有一种内置的方法来拆分C++中的字符串？

std::string str = "Hello, world!";
std::string sub = str.substr(0, 5); // sub 的值为 "Hello"

std::string str = "Hello, world!";
size_t pos = str.find(", ");
if (pos != std::string::npos) {
  std::string sub1 = str.substr(0, pos); // sub1 的值为 "Hello"
  std::string sub2 = str.substr(pos + 2); // sub2 的值为 "world!"
}

std::string str = "Hello, world!";
std::regex re(", ");
std::sregex_token_iterator it{str.begin(), str.end(), re, -1};
std::sregex_token_iterator end;
for (auto i = it; i != end; ++i) {
  std::cout << *i << std::endl;
}