Std String Find Character C++ Code Example

Example 1: c++ string contains

if (string1.find(string2) != std::string::npos) {     std::cout << "found!" << '\n'; }

Example 2: std string find character c++

// string::find #include <iostream>       // std::cout #include <string>         // std::string  int main () {   std::string str ("There are two needles in this haystack with needles.");   std::string str2 ("needle");    // different member versions of find in the same order as above:   std::size_t found = str.find(str2);   if (found!=std::string::npos)     std::cout << "first 'needle' found at: " << found << '\n';    found=str.find("needles are small",found+1,6);   if (found!=std::string::npos)     std::cout << "second 'needle' found at: " << found << '\n';    found=str.find("haystack");   if (found!=std::string::npos)     std::cout << "'haystack' also found at: " << found << '\n';    found=str.find('.');   if (found!=std::string::npos)     std::cout << "Period found at: " << found << '\n';    // let's replace the first needle:   str.replace(str.find(str2),str2.length(),"preposition");   std::cout << str << '\n';    return 0; }