Use the following standard conversion functions when you need to convert between numbers and strings:

• To convert from an integer or floating point type to a string type, use std::to_string() or std::to_wstring() as shown in the following code snippet:

        auto si = std::to_string(42);      // si="42" 
        auto sl = std::to_string(42l);     // sl="42" 
        auto su = std::to_string(42u);     // su="42" 
        auto sd = std::to_wstring(42.0);   // sd=L"42.000000" 
        auto sld = std::to_wstring(42.0l); // sld=L"42.000000"

• To convert from a string type to an integer type, use std::stoi(), std::stol(), std::stoll(), std::stoul(), or std::stoull(); refer to the following code snippet:

        auto i1 = std::stoi("42");                 // i1 = 42 
        auto i2 = std::stoi("101010", nullptr, 2); // i2 = 42 
        auto i3 = std::stoi("052", nullptr, 8);    // i3 = 42 
        auto i4 = std::stoi("0x2A", nullptr, 16);  // i4 = 42

• To convert from a string type to a floating point type, use std::stof(), std::stod(), or std::stold(), as shown in the following code snippet:

        // d1 = 123.45000000000000 
        auto d1 = std::stod("123.45"); 
        // d2 = 123.45000000000000 
        auto d2 = std::stod("1.2345e+2"); 
        // d3 = 123.44999980926514 
        auto d3 = std::stod("0xF.6E6666p3");