这个程序基本上应该从文件中读取数据，然后根据数据进行处理。它有点像一家模拟餐饮公司，变量包括成人人数、儿童人数、用餐类型（豪华或标准），一天的类型（周末[是或否]、首次存款等，以及附加费、税费、总额等在CalcData功能中根据数据进行计算（即，如果是豪华餐（D或S），价格为25.80美元，而不是21.75美元（标准餐）；如果是周末（Y或N），则附加费将添加到总账单中，并根据总金额提供折扣）。
尽管我认为我在函数中过度使用了引用，但该程序在没有错误检查部分的情况下运行良好（即检查输入是否有效-成人/儿童/初始存款金额没有负数，除了S/D和/或Y/N之外没有其他字母，等等）。我最初使用了一个返回bool的"isValid"函数和一个"outputErrorFile"函数，并在main中使用if/else-如果数据无效，则输出到错误文件，如果不是无效，则仅输出到"账单声明"文本文件。此后，我将两者组合在一个"checkValid"函数中。做同样的事情，我认为，所以没有必要有两个单独的功能。
现在，它正在将所有内容输出到错误文件中（特别是，bool变量"valid"在我的所有数据中都是false）。我确信我在里面做了一些愚蠢的事。我并不真正关心输出到控制台的内容，只关心输出到文本文件的内容。。。谢谢你的光临。
谢谢。
输入文件（成人、儿童、豪华或标准餐、周末（是/否）、初始存款）：
10 0 S Y 100.00
27 3天Y 57.50
125 17天N 0.00
4 0 S N 25.00
0 25 S Y 23.75
250 43天N 500.00
0 0 D N 0.0
10 0 R Y 10.00
17 3 D R 15.00
5 0天275.00
-3 10 D Y 20.00
14-1 S N 30.00
20 3天-10.00
#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;
void getData(int &, int &, char &, char &, float &);
void checkValid(int &, int &, char &, char &, float &, bool &);
void calcData(int, int, char, char, float, float &, float &, float &, float &);
void sendData(int, int, char, char, float, float &, float &, float &, float &);
ifstream inFile;
ofstream outFile("Billing_Statement.txt");
ofstream error_Report("Error_Report.txt");
//Declare the tax rate and weekend surcharge as constants.
const float taxRate = 0.18;
const float weekendSurcharge = .07;
int main()
{
bool valid = true;
float mealCost;
float totalTax;
float totalSurcharge;
float discountAmount;
int numAdults;
int numChildren;
char mealType;
char dayType;
float depositAmount;
cout << "nThis program will calculate data for a catering company " << endl;
outFile << " Adults " << "Children " << "Meal " << " Weekend " << setw(9) << "Deposit "
<< setw(6) << "Tax" << setw(11) << "Surcharge" << setw(10) << "Discount" << setw(12) <<
"Meal Cost" << endl;
error_Report << " Adults " << "Children " << "Meal " << " Weekend " << setw(9) <<
"Deposit " << endl;
inFile.open("file.txt");
if (!inFile) {
cout << "nError: File could not be opened. ";
exit(1);
}
while (!inFile.eof()) {
getData(numAdults, numChildren, mealType, dayType, depositAmount);
checkValid(numAdults, numChildren, mealType, dayType, depositAmount, valid);
if (valid == true)
{
calcData(numAdults, numChildren, mealType, dayType, depositAmount, totalTax,
totalSurcharge, discountAmount, mealCost);
sendData(numAdults, numChildren, mealType, dayType, depositAmount, mealCost,
totalTax, totalSurcharge, discountAmount);
}}
cout << "nA copy of this has created for your convenience in the file,
"Billing_Statement.txt "" << endl;
inFile.close();
outFile.close();
error_Report.close();
return 0;
}
void getData(int &numAdults, int &numChildren, char &mealType, char &dayType, float
&depositAmount)
{
inFile >> numAdults >> numChildren >> mealType >> dayType >> depositAmount;
}
void checkValid(int &numAdults, int &numChildren, char &mealType, char &dayType, float
&depositAmount, bool & valid)
{
if (numAdults < 0 || numChildren < 0)
valid = false;
else if (mealType != 'D' || mealType != 'S')
valid = false;
else if (dayType != 'Y' || dayType != 'N')
valid = false;
else if (depositAmount < 0)
valid = false;
else
valid = true;
if (valid == false) {
error_Report << setw(7) << numAdults << setw(9) << numChildren << setw(6) << mealType <<
setw(9) << dayType << setw(9) << right << depositAmount << setw(8) << endl;
}
}
void calcData(int numAdults, int numChildren, char mealType, char dayType, float
depositAmount, float &totalTax, float &totalSurcharge, float &discountAmount, float
&mealCost)
{
if (mealType == 'S') {
mealCost = ((numAdults * 21.75) + (numChildren * (21.75 * .60)));
totalTax = mealCost * taxRate;
mealCost += taxRate;
if (dayType == 'Y') {
totalSurcharge = mealCost * weekendSurcharge;
mealCost += totalSurcharge;
}}
else {
mealCost = ((numAdults * 25.80) + (numChildren * (25.80 * .60)));
totalTax = mealCost * taxRate;
mealCost += taxRate;
if (dayType == 'Y') {
totalSurcharge = mealCost * weekendSurcharge;
mealCost += totalSurcharge;
}
}
if (mealCost < 100) {
discountAmount = .015 * mealCost;
mealCost -= discountAmount;
}
else if (mealCost >= 100 && mealCost < 400) {
discountAmount = .025 * mealCost;
mealCost -= discountAmount;
}
else if (mealCost >= 400) {
discountAmount = .035 * mealCost;
mealCost -= discountAmount;
}
}
void sendData(int numAdults, int numChildren, char mealType, char dayType, float
depositAmount, float &mealCost, float &totalTax, float &totalSurcharge, float
&discountAmount)
{
outFile << fixed << showpoint << setprecision(2);
outFile << setw(7) << numAdults << setw(9) << numChildren << setw(6) << mealType <<
setw(9) << dayType << setw(9) << right << depositAmount << setw(8) << totalTax <<
setw(10) << totalSurcharge << setw(10) << right << discountAmount << setw(12) << right
<< mealCost << endl;
}
这似乎是您对类型的检查，例如
mealType != 'D' || mealType != 'S'
将总是产生true，因此，valid总是被设置为false。你可能是指
!(mealType == 'D' || mealType == 'S')
或用布尔逻辑重写
mealType != 'D' && mealType != 'S'
顺便说一句，你的程序中也有其他错误。例如，我有一个最讨厌的问题：使用file.eof()控制输入循环总是错误的！您将对最后一行进行两次处理，或者，如果某个地方有一个格式错误的输入，则以无限循环结束。您总是需要在尝试读取后检查输入是否成功！流不可能提前知道你要读什么，以及这是否会成功。