boost::lexical_cast

#include <cstdio>
#include <iostream>
#include <boost/lexical_cast.hpp>
#include <sstream>

using namespace std;
using namespace boost;

int main()
{
    //string 转 数值
    //lexical_cast依赖于字符流std::stringstream，其原理相当简单：把源类型读入到字符流中，再写到目标类型中。
    using boost::lexical_cast;
    int nInt = lexical_cast<int>("123");
    //等价
    int d;
    std::stringstream s;
    s << "123";
    s >> d;

    double dLong = lexical_cast<double>("3.14");
    cout << nInt << endl;
    cout << dLong << endl;

    cout << lexical_cast<string>(0x10) << endl;//16
    cout << lexical_cast<bool>(1) << endl;//1

    //异常
    try {
        nInt = boost::lexical_cast<int>("abcd");
    }
    catch (boost::bad_lexical_cast& e)
    {
        cout << e.what() << endl;
    }

    ////数值 转 string。 boost1.6.7版本，无浮点数的精度问题， 可输完整字符串
    std::string strf = boost::lexical_cast<std::string>(123.123456789);
    cout << strf << endl; //123.123456789

    return EXIT_SUCCESS;
}