为什么我的“ customer.cpp”文件中出现错误消息

Question

我不确定为什么将鼠标悬停在purchaseArray文件的string Customer::save()方法中的customer.cpp上时收到此错误消息的原因：

标识符未定义

当我将鼠标悬停在getline文件的void Customer::parse(string line)方法中的customer.cpp上时，此错误消息：

没有重载函数“ getline”的实例与参数列表匹配，参数类型为：（std :: stringstream，int，char）

Customer.cpp文件中的代码：

#include "Customer.h"
#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
#include<utility>
using namespace std;

//default constructor
Customer::Customer() {
}


//Full constructor
Customer::Customer(int customerID, string title, string name, int numOfPurchases, int purchase1, int purchase2, int purchase3, string type)
{
    this->customerID = customerID;
    this->title = title;
    this->name = name;
    this->numOfPurchases = numOfPurchases;
    purchases = new int[3];
    purchases[0] = purchase1;
    purchases[1] = purchase2;
    purchases[2] = purchase3;
    this->type = type;
}

Customer::Customer(const Customer& source) //copy constructor
{
    cout << "copy constructor called" << endl;
    this->customerID = source.customerID;
    this->title = source.title;
    this->name = source.name;
    this->numOfPurchases = source.numOfPurchases;
    this->purchases = new int[3];
    purchases[0] = source.purchases[0];
    purchases[1] = source.purchases[1];
    purchases[2] = source.purchases[2];
    this->type = source.type;
}

//overloaded assignment operator=
Customer& Customer::operator= (Customer& otherCustomer)
{
    cout << "Overloaded assignment operator= called" << endl;

    //self-assignment guard
    if (this == &otherCustomer)
        return *this;  //refernce to the same object

   // copy data from the source (rhs) to this object (the destination)
    name = otherCustomer.name;

    //must make a new scores object to store a copy of the other student 
    if (purchases != nullptr)
        delete[] purchases;

    purchases = new int[3];
    for (int i = 0; i < 3; i++) {
        purchases[i] = otherCustomer.purchases[i];
    }

    //return this existing object so we can chain this operator 
    return *this;
}

string Customer::save()
{
    stringstream out;
    out << this->customerID << ";";
    out << this->title << ";";
    out << this->name << ";";
    out << this->numOfPurchases << ";";
    int* purchases = 0;
    purchases = purchases | (purchaseArray[0] << 24);
    purchases = purchases | (purchaseArray[1] << 16);
    purchases = purchases | (purchaseArray[2] << 8);
    out << this->type << ";";
    out.flush();
    return out.str();
}

void Customer::parse(string line)
{
    stringstream in(line);
    string customerIDLine;
    getline(in, customerIDLine, ';');
    customerID = stoi(customerIDLine);
    getline(in, title, ';');
    getline(in, name, ';');

    int numOfPurchases;
    getline(in, numOfPurchases, ';');
    int s = stoi(numOfPurchases);

    purchasesArray[0] = (s & (255 << 16)) >> 16;
    purchasesArray[1] = (s & (255 << 8)) >> 8;
    purchasesArray[2] = s & 255;

    getline(in, type, ';');
}  

Customer::~Customer() {
    cout << "Destructor ~Customer called" << endl;
    delete[] purchases;
}

// Overloaded insertion operator  (Outputs Character object data as an output stream)
// Defined in header file as a  "friend" function, as it is not a member function
//
ostream& operator<<(ostream& out, Customer& customer)
{
    cout << "Customer details ( output by insertion operator<< )" << endl;
    cout << "Customer ID: " << customer.customerID << endl;
    cout << "Title: " << customer.title << endl;
    cout << "Name: " << customer.name << endl;
    cout << "Number of purchases: " << customer.numOfPurchases << endl;
    cout << "Purchases: ";
    for (int i = 0; i < 3; i++)
    {
        if (i > 0) cout << ",";
        cout << customer.purchases[i];
    }
    cout << "Type: " << customer.type << endl;
    
    return out;
}


istream& operator>> (istream& in, Customer& customer)
{
    cout << "Enter Customer details ( using the extraction operator>> )" << endl;
    cout << "Enter Customer ID: " << endl;
    cin >> customer.customerID;
    cout << "Enter Title: " << endl;
    getline(cin, customer.title);
    cout << "Enter Name: " << endl;
    getline(cin, customer.name);
    cout << "Enter Number of Purchases: ";
    cin >> customer.numOfPurchases; 
    cout << "Enter Purchases: ";
    cin >> customer.purchases[0];
    cin >> customer.purchases[1];
    cin >> customer.purchases[2];
    cout << "Enter Type";
    getline(cin, customer.type);
    cout << endl;

    return in;
}

int Customer::getCustomerID()
{
    return customerID;
}

string Customer::getTitle()
{
    return title;
}

string Customer::getName()
{
    return name;
}

int Customer::getNumOfPurchases()
{
    return numOfPurchases;
}

int* Customer::getPurchases()
{
    return purchases;
}

string Customer::getType()
{
    return type;
}

void Customer::setCustomerID(int customerID)
{
    if (customerID < 1) {
        cout << "Customer ID has to be equal to 1 or more" << endl; //Changed all the "throw invalid_argument" messages to cout as they were causing an issue with my main.cpp file and an abort message kept appearing every time I ran my main.cpp file.
    }
    this->customerID = customerID;
}

void Customer::setTitle(string title)
{
    if (title.length() < 2) {
        cout << "Title has to be more than or equal to 2 characters" << endl;
    }
    this->title = title;
}

void Customer::setName(string name)
{
    if (name.length() < 4) {
        cout << "Length of name should be more than or equal to 4 characters" << endl;
    }
    this->name = name;
}

//Got help ith this on stack overflow as I was using "&&" instead of using "||" for the if statement
void Customer::setNumOfPurchases(int numOfPurchases)
{
    if(numOfPurchases <0 || numOfPurchases > 10000){
        cout << "Number of purchases should be between 0 to 10000" << endl;
    }
    this->numOfPurchases = numOfPurchases;
}

void Customer::setPurchases(int purchase1, int purchase2, int purchase3)
{
    if (purchase1 < 0 || purchase2 < 0 || purchase3 < 0) {
        cout << "Purchases must be more than or equal to zero" << endl;
    }
}

//Got help from stack overflow on comparing strings as I originally didnt use "type.compare"
void Customer::setType(string type) {
    if (type.compare("New") !=0 || type.compare("Either") !=0) {
        cout << "Type of purchase has to be New or Either" << endl;
    }
}

Customer.h文件中的代码：

#pragma once
#include<iostream>
using namespace std;
#include<string>

class Customer
{
private:
    int customerID;
    string title;
    string name;
    int numOfPurchases;
    int* purchases;
    string type;

public:
    Customer(); // default constructor
    Customer(int customerID, string title, string name, int numOfPurchases, int purchase1, int purchase2, int purchase3, string type);
    
    //copy overload assignment
    Customer& operator=(Customer& otherCustomer);
    Customer(const Customer& source);

    string save();
    void parse(string line);
    ~Customer(); //destructor


    //Getters and Setters
    void setCustomerID(int customerID);
    void setTitle(string title);
    void setName(string name);
    void setNumOfPurchases(int numOfPurchases);
    void setPurchases(int purchase1, int purchase2, int purchase3);
    void setType(string type);

    int getCustomerID();
    string getTitle();
    string getName();
    int getNumOfPurchases();
    int* getPurchases();
    string getType();

    void printCustomer() {
        cout << customerID << "," << title << "," << name << "," << numOfPurchases << "," << purchases << "," << type << endl;
    }

    

    friend std::ostream& operator<<(std::ostream& out, Customer& customer); // overloaded operator<<
    friend istream& operator>> (istream& in, Customer& customer); // overloaded operator >>
};

来自Main.cpp文件的代码：

// Repeat_Assessment_C++_AislingSmith.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <vector>
#include "Customer.h"
using namespace std;


void OutputFileStream();
void parseLine(const string& str);
void InputFileStream();
void save(vector<Customer> customers);
void load(vector<Customer>& customers);
void addCustomer(vector<Customer>& vect);
//void printActions();


void OutputFileStream()
{
    cout << "Creating and writing to file: Customer.txt" << endl;

    ofstream outStream("customers.txt");  // write mode (overwrites existing data)

    if (outStream.good())
    {
        int customerID = 150033;
        outStream << "This is a line of text.\n";
        outStream << "This is another line of text.\n";
        outStream << "This is a line of text.\n";
        int numOfPurchases = 4;
        int purchases = 0;
        outStream << customerID << "Mr" << "Jack" << "New" << numOfPurchases << purchases << endl;

        outStream.close(); //  close file
        cout << "File written.\n" << endl;
    }
    else
        cout << "Unable to open file";
}

void parseLine(const string& str) {

    stringstream strStream(str); //create string stream from the string
   // int customerID;
    string title;
    string name;
    string type;
    //int numOfPurchases;
    //int purchases;
    string s;
   
    int customerID = 150033;
    getline(strStream, s, ';');
    customerID = stoi(s);

    getline(strStream, title, ';');
    getline(strStream, name, ';');
    getline(strStream, type, ';');

    int numOfPurchases = 4;
    getline(strStream, s, ';');
    numOfPurchases = stoi(s);

    int purchases = 0;
    getline(strStream, s, ';');
    purchases = stoi(s);
    int* purchasesArray = new int[3];
    purchasesArray[0] = (purchases & (255 << 16)) >> 16;
    purchasesArray[1] = (purchases & (255 << 8)) >> 8;
    purchasesArray[2] = purchases & 255;
    for (int i = 0; i < 3; i++)
    {
        int purchasesArray[3];
    }

    cout << " CustomerID: " << customerID << "Title:" << title << " Name: " << name << " Type:" << type << " Number of Purchases: " << numOfPurchases << "Purchases: " << purchases << endl;
}

void InputFileStream() {
    cout << "Reading from a semi-colon delimited txt file" << endl;

    string line;
    ifstream inStream("customers.txt"); //opens file as an input file stream
    if (inStream.good()) //if the file is opened successfully and not empty
    {
        while (getline(inStream, line)) //reads line until false return
        {
            parseLine(line);
        }
        inStream.close();
    }
    else
        cout << "unable to open file or the file is empty!";
}

void save(vector<Customer> customers)
{
    ofstream out("customers.txt");
    if(out)
    {
        for (Customer& c : customers)
        {
            out << c.save();
        }
        out.flush();
        out.close();
    }
    else
    {
        cout << "Error Writing to File" << endl;
    }
}

void load(vector<Customer>& customers)
{
    ifstream in("customers.txt");
    if (in) {
        string line;
        while (!in.eof())
        {
            getline(in, line);
            if (line != "")
            {
                Customer c;
                c.parse(line);
                customers.push_back(c);
            }
        }
    }
}

void addCustomer(vector<Customer>& customers) {
    Customer customer;
    cin >> customer;
    customers.push_back(customer);
    
}



int main()
{
    InputFileStream();
    vector<Customer> customers;
    Customer c;

    Customer cust1;

    cust1.setCustomerID(150032);
    cust1.setTitle("Mr");
    cust1.setName("Joey");
    cust1.setNumOfPurchases(3);
    cust1.setPurchases(366, 352, 334);
    cust1.setType("New");

    cout << cust1.getCustomerID() << endl;
    cout << cust1.getTitle() << endl;
    cout << cust1.getName() << endl;
    cout << cust1.getNumOfPurchases() << endl;
    cout << cust1.getPurchases() << endl;
    cout <<  cust1.getType() << endl;
   
    


    return 0;
   

}

Answer 1

第一个问题

第一个错误非常清楚，purchaseArray没有定义（至少在您在此处显示的代码中没有定义），您可能只想说purchases或this->purchases？尽管我不知道您尝试使用int *purchases来达到什么目的。

第二个问题

发生第二个错误，因为您尝试从流中读取整数的方式存在缺陷。 与Customer::parse

中的这段代码有关

int numOfPurchases; // declare int 
getline(in, numOfPurchases, ';'); // error, second parameter must be std::string!
int s = stoi(numOfPurchases); // numOfPurchases is already an int

您可能想要这个：

std::string numOfPurchasesBuf; // temporary buffer
getline(in, numOfPurchasesBuf, ';'); // read data to string
int s = stoi(numOfPurchasesBuf); // convert to int

并且由于所有这些行都读取了一个成员变量，因此您可能还需要设置该成员变量：

this->numOfPurchases = s;