Question

我似乎无法获得“满员” 显示第一个和最后一个的串联。它编译但是当我运行它时它将显示为空白。你能告诉我为什么吗？试着把它弄清楚几个小时。

以下是我的陈词滥调

#include <iostream>
#include <iomanip>
#include <string>

using namespace std;

#define tax  0.30
#define parking_deductions 10.00
#define overtime_hours 40  
#define max_hours 60 
#define max_pay 99  
string namestring( string first, string last, string full);

我正在尝试将此模块传递给我的主要

string namestring(string first, string last, string full)
{
    //input name
    cout << "What is your first name? " << endl;
    cout << "first name: " << endl;
    cin >> first;

    cout << "What is your last name? " << endl;
    cout << "last name: " << endl;
    cin >> last;

    //process name
    full = last + " " + first;
    return full;
}

通过这样称呼

namestring(first, last, full );

我期望用户输入的全名显示在

下面

        cout << left << fixed << "            " << "Reg." << "  " << "      Ovt." << "  Hourly" << "   Net" << "  " << "              Gross" << endl;
    cout << left << fixed << setprecision(2) << setw(10) << "Name                " << "  Hours" << "  Hours" << " Rate" << "     Pay" << "   Taxes" << "     Deduct" << "    Pay" << endl;
    cout << left << fixed << setprecision(2) << setw(10) << "====================" << "  " << "=====" << "  " << "=====" << " " << "=====" << "  " << "======" << "  " << "======" << "  " << "  " << "========" << "  " << "=======" << endl;
    cout << left << setprecision(2) << setw(20) << full << right << " " << right << setw(4) << hours << right << "   " << right << overtime << "  " << right << pay << "  " << right << net_pay << "  " << right << taxs << "    " <<  right << parking_deductions << "     " << right << gross_pay << right << endl;
    cout << endl;
    cout << endl;

Answer 1

我假设这里的目标是获得以下3个字符串，

First Name
Last Name
Full Name

为此，您需要通过引用而不是值传递参数：

void namestring(string& first, string& last, string& full)
{
    //input name
    cout << "What is your first name? " << endl;
    cout << "first name: " << endl;
    cin >> first;

    cout << "What is your last name? " << endl;
    cout << "last name: " << endl;
    cin >> last;

    //process name
    full = last + " " + first;;
}

如果您通过引用传递“完整”字符串，也不需要返回字符串，因为该函数将为您填充。

Answer 2

string namestring(string first, string last, string& full)
//input name
{    
    cout << "What is your first name? " << endl;
    cout << "first name: " << endl;
    cin >> first;

    cout << "What is your last name? " << endl;
    cout << "last name: " << endl;
    cin >> last;

    //process name
    full = last + " " + first;
    return full;
}

您按价值传递full。所以它是被修改的函数的本地副本。你需要它通过引用传递。如果您还想要第一个和最后一个值，您还需要通过引用传递它。

有人告诉我为什么我的字符串在传递参数后是空白的？

2 个答案: