小编Jos*_*171的帖子

我正在[Bjarne_Stroustrup]Programming-Principles-and-Practice-Using-C++从2008年开始编写本书,第5章称为Errors使用std_lib_facilities.h和函数调用error.

这是一个例子:

if(x<=0) error("non-positive x");
if(y<=0) error("non-positive y");
int area1=area(x,y);

由于我使用的是没有的Visual Studio 2012std_lib_facilities.h,因此此错误处理程序无法正常工作!什么是iostream错误处理功能,我在哪里可以找到并研究它？

这是iostream中的一个错误吗？...

        #include<iostream>
        void money_conversion (){

        constexpr double dollars_in_yen=0.01;
        constexpr double dollars_in_euro=1.16;
        constexpr double dollars_in_pound=1.33;
        std::cout<<"Supported valutes : yen ('y'), euros('e'), pounds('p').\n";
        std::cout<<"Please enter the value + valute that you want to convert into dollars! :";
        double value=1;
        char valute=0;
        while(true){
        std::cin>>value>>valute;
        if(valute=='y')
            std::cout<<"\n\n"<<value<<" yens is "<<value*dollars_in_yen<<" dollars. \n";
        else if(valute=='e')
            std::cout<<"\n\n"<<value<<" euros is "<<value*dollars_in_euro<<" dollars. \n";
        else if(valute=='p')
            std::cout<<"\n\n"<<value<<" pounds is "<<value*dollars_in_pound<<" dollars. \n";
        else
            std::cout<<"\n\nSorry, unknown valute ("<<valute<<").\n";
        }

    }


    int main(){

        money_conversion();
        return 0;

    }

键盘输入时

• '5p'或

• '5 …