该程序使用类，并从文件中获取员工的信息。我也提到了下面的文件。我也提到了即使有错误我也收到的输出。输出中也有问题，但是我认为这是由于信息错误而导致的。
在运行该程序时，出现以下错误消息：
Error: Run-Time Check Failure #2 - Stack around the variable 'info' was corrupted.
还有此消息：
Unhandled exception at 0x00950A89 in employee.exe: Stack cookie instrumentation code detected a stack-based buffer overrun.
//该程序使用的文件是：
A.Smith 20001 25 40
T.Philip 20002 20 35
S.LOng 20003 15 50
G.Santos 20004 30 30
F.Farkas 20005 22 55
//即使出现错误，运行后的输出是：
This week's employee history
Name Id Rate Hours
* A.Smith 20001 $25/h 40h
* T.Philip 20002 $20/h 35h
* S.LOng 20003 $15/h 50h
* G.Santos 20004 $30/h 30h
* F.Farkas 20005 $22/h 55h
This week's payment
Name Payment
* ╠╠╠╠╠╠╠╠ $0 <----------There is this error too
* T.Philip $700
* S.LOng $825
* G.Santos $900
* A.Smith $1000
* The average wages of the employees: $685.00
//代码是：
/*
#include "pch.h"
#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <string>
#include<iomanip>
*/
using namespace std;
struct records {
char name[50] = {};
char id[5] = {};
int rate = 0;
int hours = 0;
int pay = 0;
};
void take(records array[], const int a);
int calculator(records array[], const int a);
void swap(records array[], const int a);
double Average(records array[], int a);
ifstream infile;
int main()
{
const int n = 5;
这是第一次声明信息：
struct records info[n];
double averageWages;
int overTime = 0, i;
infile.open("Project 3.dat");
cout << "\n This week's employee history \n" << endl;
if (infile.is_open()) {
cout << " Name Id Rate Hours " << endl;
此处的take函数使用该结构的信息：
take(info, n);
cout << endl << endl;
cout << "This week's payment\n" << endl;
cout << " Name Payment" << endl;
这里其他功能也使用信息：
calculator(info, n);
swap(info, n);
for (i = 0; i < n; i++) {
cout << "*" << setw(10) << info[i].name << setw(10) << "$" << info[i].pay << endl;
}
averageWages = Average(info, n);
cout << "\n\n" << "* The average wages of the employees: $" << averageWages << endl << endl;
}
else {
cerr << "Error! file cannot open." << endl;
exit(1);
}
return 0;
}
//记录：
void take(records array[], const int a) {
for (int i = 0; i < a; i++) {
while (infile >> array[i].name >> array[i].id >> array[i].rate >> array[i].hours) {
cout << "*" << setw(9) << array[i].name << setw(10) << array[i].id << setw(10) << "$" << array[i].rate << "/h" << setw(10) << array[i].hours << "h " << endl;
}
} infile.close();
}
//交换记录以根据收到的总付款进行安排
void swap(records array[], const int a) {
bool tf; //true or false
do {
tf = false;
for (int i = 0; i < a; i++) {
if (array[i].pay > array[i + 1].pay) {
swap(array[i], array[i + 1]);
tf = true;
}
}
} while (tf);
records temp;
for (int i = 0; i < a - 1; ++i)
{
for (int j = i + 1; j < a; ++j)
{
if (array[i].pay > array[j].pay)
{
temp = array[i];
array[i] = array[j];
array[j] = temp;
}
}
}
}
To calculate average:
double Average(records array[], const int a) {
double total = 0;
double average;
for (int i = 0; i < a; i++) {
total = total + (array[i].pay);
average = total / a;
}
cout.setf(ios::fixed);
cout.setf(ios::showpoint);
cout.precision(2);
return (total / a);
}
//计算工资：
int calculator(records array[], const int a) {
infile.open("Project 3.dat");
if (infile.is_open()) {
for (int i = 0; i < a; i++) {
infile >> array[i].name >> array[i].id >> array[i].rate >> array[i].hours;
if (array[i].hours > 40) {
int overTime = (array[i].hours - 40)*1.5;
array[i].pay = ((array[i].rate) * 40) + (overTime*(array[i].rate));
}
else {
array[i].pay = (array[i].rate)*(array[i].hours);
}
}
for (int i = 0; i < a; i++) {
return (array[i].pay);
}
}
}
答案 0 :(得分：0)
使用该碎片代码很难找到所有潜在的问题，但是最好使用std::string而不是char[]。它们更安全，并且具有很多内置功能。它们与misc配合也很好。 STL中的功能。
您的struct records info[n];仅包含n（5）个元素。如果您想向文件中添加更多条目，请使用标准容器，例如std::vector。
读取和写入文件通常可以使用自定义流运算符完成，并且您必须处理许多记录的所有免费功能都可以收集在其自己的类中。我已经制作了一个record结构和一个Records类，以演示如何将它们一起使用。
#include <iostream>
#include <vector>
#include <iomanip>
#include <sstream>
#include <fstream>
#include <numeric>
#include <algorithm>
#include <functional>
struct record {
std::string name{};
std::string id{};
int rate = 0;
int hours = 0;
int pay = 0;
// stream operators for reading/writing a record
friend std::istream& operator>>(std::istream&, record&);
friend std::ofstream& operator<<(std::ofstream&, const record&);
friend std::ostream& operator<<(std::ostream&, const record&);
};
// populate a record from an istream
std::istream& operator>>(std::istream& is, record& r) {
std::string line;
// get a line and check that it's > 30 chars long
if(std::getline(is, line) && line.size()>30) {
// extract the name and remove trailing spaces
r.name = line.substr(0, 30);
auto pos = r.name.find_last_not_of(' ');
if(pos != std::string::npos)
r.name = r.name.substr(0, pos+1);
// put the rest of the line in a stringstream
std::stringstream ss(line.substr(30));
// and extract the rest of the fields
if(ss >> r.id >> r.rate >> r.hours) {
// calculate pay
r.pay = r.rate * r.hours;
} else { // if extraction fails, set the stream in fail mode
is.setstate(std::ios_base::failbit);
}
} else is.setstate(std::ios_base::failbit);
return is;
}
// streaming a record to an ofstream (like a file)
std::ofstream& operator<<(std::ofstream& os, const record& r) {
os << std::setw(30) << std::left << r.name.substr(0, 30) << r.id << " " << r.rate << " " << r.hours << "\n";
return os;
}
// streaming a record to a generic ostream (like std::cout)
std::ostream& operator<<(std::ostream& os, const record& r) {
os << "* " << std::setw(30) << std::left << r.name << std::right << r.id
<< " $" << r.rate << "/h " << r.hours << "h $" << std::setw(4) << r.pay;
return os;
}
class Records { // a class to maintain a number of "record"s
std::vector<record> m_records{}; // stores all "record"s
public:
Records(const std::string& filename) {
record tmp;
std::ifstream e(filename); // open file
// and extract one record at a time and put it in m_records.
while(e>>tmp) m_records.emplace_back(std::move(tmp));
}
// sum on any member in "record"
template <typename field>
auto Sum(field f) const {
return std::accumulate(m_records.begin(), m_records.end(), 0,
[&](int a, const record& b) { return a + (b.*f); });
}
// average of any member in "record"
template <typename field>
auto Average(field f) const {
return static_cast<double>(Sum(f)) / m_records.size();
}
// sorting on any member in "record"
template <typename field, typename T>
void Sort(field f, const T& cmp) {
std::sort(m_records.begin(), m_records.end(),
[&](const record& a, const record& b){ return cmp(a.*f, b.*f); });
}
// return the number of "record" elements
std::vector<record>::size_type size() const { return m_records.size(); }
// access an element via subscript
record& operator[](std::vector<record>::size_type idx) { return m_records[idx]; }
const record& operator[](std::vector<record>::size_type idx) const { return m_records[idx]; }
// iterators to use in for-loops
std::vector<record>::const_iterator cbegin() const noexcept { return m_records.cbegin(); }
std::vector<record>::const_iterator cend() const noexcept { return m_records.cend(); }
std::vector<record>::const_iterator begin() const noexcept { return cbegin(); }
std::vector<record>::const_iterator end() const noexcept { return cend(); }
std::vector<record>::iterator begin() noexcept { return m_records.begin(); }
std::vector<record>::iterator end() noexcept { return m_records.end(); }
// stream operator to show all records
friend std::ostream& operator<<(std::ostream&, const Records&);
};
std::ostream& operator<<(std::ostream& os, const Records& R) {
os << " Name Id Rate Hrs Pay\n";
for(const auto& r : R) std::cout << r << "\n";
os << std::setprecision(2) << std::fixed;
os << "Average pay : $" << std::setw(7) << R.Average(&record::pay) << "\n";
os << " rate : $" << std::setw(7) << R.Average(&record::rate) << "\n";
os << " hours worked: " << std::setw(7) << R.Average(&record::hours) << "h\n";
return os;
}
int main() {
// create a "Records" entity called "info" by reading a file
Records info("Project 3.dat");
// misc sorting and showing the result
std::cout << "Sorted as read from the file:\n";
std::cout << info;
std::cout << "\nSorted according to name:\n";
info.Sort(&record::name, std::less<std::string>());
std::cout << info;
std::cout << "\nSorted according to id:\n";
info.Sort(&record::id, std::less<std::string>());
std::cout << info;
std::cout << "\nSorted according to pay:\n";
info.Sort(&record::pay, std::greater<int>());
// output example using iterators:
for(auto& rec : info) {
std::cout << rec << "\n";
}
std::cout << "\nSorted according to rate:\n";
info.Sort(&record::rate, std::greater<int>());
std::cout << info;
std::cout << "\nSorted according to hours:\n";
info.Sort(&record::hours, std::greater<int>());
std::cout << info;
// example using subscript, operator[]
if(info.size()>2) {
std::cout << "\ninfo[2] = " << info[2] << "\n";
}
}