如果我输入
说明：苹果
数量：10
批发成本：30
零售成本：20
添加日期：十二月
这些是我的 .dat 文件中的内容：
1Apple103020十二月
但是当我加载我的程序时，它没有正确加载结构，导致我的列表中有 0 个项目。这是它应该看起来的样子，还是我做错了什么。
代码：
#include "stdafx.h"
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
using namespace System;
using namespace std;
#pragma hdrstop
bool isValidChoice(int size, int choice);
template<typename T>
void writeVector(ofstream &out, const vector<T> &vec);
template<typename T>
vector<T> readVector(ifstream &in);
template<typename T>
vector<T> addItem(vector<T> &vec);
template<typename T>
void printItemDescriptions(vector<T> &vec);
template<typename T>
int displayRecord(vector<T> &vec);
struct InventoryItem {
string Description;
int Quantity;
int wholesaleCost;
int retailCost;
string dateAdded;
} ;
int main(void)
{
cout << "Welcome to the Inventory Manager extreme! [Version 1.0]" << endl;
ifstream in("data.dat");
if (in.is_open()) { cout << "File \'data.dat\' has been opened successfully." << endl; } else { cout << "Error opening data.dat" << endl;}
cout << "Loading data..." << endl;
vector<InventoryItem> structList = readVector<InventoryItem>( in );
cout <<"Load complete." << endl << endl;
in.close();
while (1)
{
string line = "";
cout << "There are currently " << structList.size() << " items in memory.";
cout << endl << endl;
cout << "Commands: " << endl;
cout << "1: Add a new record " << endl;
cout << "2: Display a record " << endl;
cout << "3: Edit a current record " << endl;
cout << "4: Delete a record " << endl;
cout << "5: Save current information " << endl;
cout << "6: Exit the program " << endl;
cout << endl;
cout << "Enter a command 1-6: ";
getline(cin , line);
int rValue = atoi(line.c_str());
system("cls");
ofstream out("data.dat");
switch (rValue)
{
case 1:
addItem(structList);
break;
case 2:
displayRecord(structList);
break;
case 3:
break;
case 4:
break;
case 5:
if (!structList.size()) { cout << "There are no items to save! Enter one first!" << endl << endl; system("pause"); system("cls"); break; }
writeVector(out , structList);
break;
case 6:
return 0;
default:
cout << "Command invalid. You can only enter a command number 1 - 6. Try again. " << endl;
}
out.close();
}
system("pause");
return 0;
}
template<typename T>
void writeVector(ofstream &out, const vector<T> &vec)
{
out << vec.size();
for(vector<T>::const_iterator i = vec.begin(); i != vec.end(); i++)
{
out << *i;
}
cout << "Save completed!" << endl << endl;
}
ostream &operator<<(ostream &out, const InventoryItem &i)
{
out << i.Description;
out << i.Quantity;
out << i.wholesaleCost << i.retailCost;
out << i.dateAdded;
return out;
}
istream &operator>>(istream &in, InventoryItem &i)
{
in >> i.Description;
in >> i.Quantity;
in >> i.wholesaleCost >> i.retailCost;
in >> i.dateAdded;
return in;
}
template<typename T>
vector<T> readVector(ifstream &in)
{
size_t size;
if (in.fail())
{
in >> size;
} else {
size = 0;
}
vector<T> vec;
vec.reserve(size);
for(unsigned int i = 0; i < size; i++)
{
T tmp;
in >> tmp;
vec.push_back(tmp);
}
return vec;
}
template<typename T>
vector<T> addItem(vector<T> &vec)
{
system("cls");
string word;
unsigned int number;
InventoryItem newItem;
cout << "-Add a new item-" << endl << endl;
cout << "Enter the description for the item: ";
getline (cin , word);
newItem.Description = word;
cout << endl;
cout << "Enter the quantity on hand for the item: ";
getline (cin , word);
number = atoi(word.c_str());
newItem.Quantity = number;
cout << endl;
cout << "Enter the Retail Cost for the item: ";
getline (cin , word);
number = atoi(word.c_str());
newItem.retailCost = number;
cout << endl;
cout << "Enter the Wholesale Cost for the item: ";
getline (cin , word);
number = atoi(word.c_str());
newItem.wholesaleCost = number;
cout << endl;
cout << "Enter current date: ";
getline (cin , word);
newItem.dateAdded = word;
vec.push_back(newItem);
return vec;
}
template<typename T>
void printItemDescriptions(vector<T> &vec)
{
int size = vec.size();
if (size)
{
cout << "---------------------------------" << endl;
cout << "| ~ Item Descriptions ~ |" << endl;
cout << "---------------------------------" << endl;
cout << "*********************************" << endl;
for (int i = 0 ; i < size ; i++)
{
cout << "(" << i+1 << ")" << ": " << vec[i].Description << endl;
}
cout << "*********************************" << endl << endl;
}
}
template<typename T>
int displayRecord(vector<T> &vec)
{
string word = "";
string quit = "quit";
int choice = 1;
int size = vec.size();
if (size)
{
printItemDescriptions(vec);
cout << endl;
while (1)
{
cout << "Type \"exit\" to return to the Main Menu." << endl << endl;
cout << "Enter \"list\" to re-display the items." << endl << endl;
cout << endl;
cout << "Pick the number of the item you would like to display: ";
getline (cin , word);
if (convertToLower(word) == "exit") { system("cls"); return 0; }
if (convertToLower(word) == "list") { system("cls"); displayRecord(vec); }
choice = atoi(word.c_str());
if (isValidChoice(size, choice))
{
system("cls");
cout << endl << "[Item (" << choice << ") details] " << endl << endl;
cout << "******************" << endl;
cout << "* Description * " << vec[choice-1].Description << endl;
cout << "******************" << endl << endl;
cout << "******************" << endl;
cout << "*Quantity On Hand* " << vec[choice-1].Quantity << endl;
cout << "******************" << endl << endl;
cout << "******************" << endl;
cout << "* Wholesale Cost * " << vec[choice-1].wholesaleCost << endl;
cout << "****************** " << endl << endl;
cout << "******************" << endl;
cout << "* Retail Cost * " << vec[choice-1].retailCost << endl;
cout << "****************** " << endl << endl;
cout << "******************" << endl;
cout << "* Data Added * " << vec[choice-1].dateAdded << endl;
cout << "****************** " << endl << endl;
} else { system("cls"); cout << "That item doesn't exist!" << endl; cout << "Pick another item or enter \"list\" to see available items." << endl << endl; }
}
} else { cout << "There are currently no items to display." << endl << endl; system("pause"); system("cls"); return 0; }
return 1;
}
bool isValidChoice(int size, int choice)
{
for (int i = 0 ; i <= size ; i++)
{
if (choice == size) { return true; }
}
return false;
}
string convertToLower(string word)
{
for (unsigned int i = 0 ; i < word.size() ; i++)
{
word[i] = tolower(word[i]);
}
return word;
}