【发布时间】：2021-09-02 00:15:44
【问题描述】：
我正在尝试将类的指针存储在向量中，但出现错误
未定义模板'std::__1::vector
- '的隐式实例化
代码是：
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
class Item{
private:
string itemName;
float itemPrice;
int itemQuantity;
public:
Item(string name = "NULL", float price = 0, int quantity = 0){
itemName = name;
itemPrice = price;
itemQuantity = quantity;
}
friend ofstream & operator<<(ofstream &ofs, Item &i);
friend ifstream & operator>>(ifstream &ifs, Item &i);
friend ostream & operator<<(ostream &os, Item &i);
};
ofstream & operator<<(ofstream & ofs, Item &i){
ofs << i.itemName << endl;
ofs << i.itemPrice << endl;
ofs << i.itemQuantity << endl;
return ofs;
}
ostream & operator<<(ostream &os, Item &i){
os << i.itemName << endl;
os << i.itemPrice << endl;
os << i.itemQuantity << endl;
return os;
}
ifstream & operator>>(ifstream & ifs , Item & i){
ifs >> i.itemName;
ifs >> i.itemPrice;
ifs >> i.itemQuantity;
return ifs;
}
int main() {
int n;
string name;
float price;
int qty;
cout<<"Enter number of Item:";
cin>>n;
vector<Item *> items;
cout<<"Enter All Item "<<endl;
for(int i=0;i<n;i++)
{
cout<<"Enter "<<i+1<<" Item Name , price and quantity";
cin>>name;
cin>>price;
cin>>qty;
items.push_back(new Item(name,price,qty));
}
ofstream fos("Items.txt");
for(int i=0;i<n;i++)
{
fos<<*items[i];
}
Item item;
ifstream fis("Items.txt");
for(int i=0;i<3;i++)
{
fis>>item;
cout<<"Item "<<i<<item<<endl;
}
}
这看起来像是一个基本错误，但我找不到解决方法。如何将用户定义类的指针存储在向量中？是我的语法关闭还是向量不能那样工作？
【问题讨论】：
-
你不见了
#include <vector> -
在明显的
#include <vector>之后，它为我编译并运行。