stringstream类操作字符串流

 C++ Code 

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/* <sstream>库定义了三种类：
    istringstream
    ostringstream
    stringstream

   分别用来进行字符串流的输入、输出和输入输出操作。
*/

#include <string>       // std::string
#include <iostream>     // std::cout
#include <sstream>      // std::stringstream, std::stringbuf

template<typename out_type, typename in_value>
out_type convert(const in_value& t)
{
    std::stringstream stream;
    stream << t;        //向流中传值
    out_type result;    //这里存储转换结果
    stream >> result;   //向result中写入值
    return result;
}

int main ()
{
    std::stringstream ss;

    //void str (const string& s);
    ss.str("Michael Joessy");

    //string str() const;
    std::string str = ss.str();
    std::cout << str << std::endl;

    //void clear (iostate state = goodbit);
    ss.clear();
    ss.str("");

    //使用stringstream对象简化类型转换
    double d;
    std::string strSalary;
    std::string myStr = "12.56";
    d = convert<double>(myStr);
    strSalary = convert<std::string>(10000);
    std::cout << strSalary << std::endl;

    //operator<<
    std::stringstream strbuf;
    strbuf << "Good Good Study";
    strbuf << ",";
    strbuf << "Day Day Up!";
    std::cout << strbuf.str() << std::endl;

    std::cin.get();
    return 0;
}