没有重载函数的实例匹配参数列表，参数类型是：(std::ifstream, std::string, char)

Question

我尝试运行程序将 txt 文件加载到链表中，但卡在了“getline”错误中。在 readLine 函数中，我尝试获取 txt 文件中的内容，但它不允许我这样做。有谁知道如何解决这一问题？我试图搜索问题并阅读有关它的答案，但我仍然不知道如何解决问题。提前致谢。

Linkedlist.h

#include "LinkedList.h"
Node* Node::createNode(Item newData)
{
    Node* point = new Node;
        if (point == nullptr)
        {
            cout << "Failed." << endl;
            exit(EXIT_FAILURE);
        }
        point->data = newData;
        point->setNext(nullptr);
        return point;
}

void LinkedList::createList(LinkedList& list)
{
    list.head = nullptr;
    list.tail = nullptr;
}
void LinkedList::insertHead(LinkedList& list, Node* point)
{
    if (list.head == nullptr)
    {
        list.head = list.tail = point;
    }
    else
    {
        point->setNext(head);
        list.head = point;
    }
}
void LinkedList::appenTail(LinkedList& list, Node* point)
{
    if (list.head == nullptr)
    {
        list.head = point;
        list.tail = point;
    }
    else
    {
        list.tail->setNext(point);
        list.tail = point;
    }
}
void LinkedList::readLine(ifstream& file, Item& item)
{
    **getline(file, item.getItemId(), ',');
    getline(file, item.getTitle(), ',');
    getline(file, item.getLoan(), ',');
    getline(file, item.getCopy(), ',');
    getline(file, item.getFee(), ',');
    getline(file, item.getGenre(), ',');**
}

void LinkedList::readAllFile(ifstream& file, LinkedList& list)
{
    while (!file.eof())
    {
        Node* point = new Node;
        Item item;
        Node node;
        readLine(file, item);
        point = node.createNode(item);
        appenTail(list, point);
    }
}

void LinkedList::printOneLine(Item item)
{
    cout << item.getItemId() << ',' << item.getTitle() << ',' << item.getLoan() << ',' << item.getCopy() << ',' << item.getFee() << ',' << item.getGenre();
}

void LinkedList::printAll(LinkedList list)
{
    for (Node* point = list.head; point != NULL; point = point->getNext())
    {
        printOneLine(point->getData());
    }
}

Item.h

#pragma once
#include <iostream>
#include <fstream>
#include <string>

using namespace std;

class Item
{
protected:
    string itemId, title, type, loan, num_copy, fee, genre;
public:
    Item() {}
    Item(string itemId, string title, string type, string loan, string num_copy, string fee, string genre)
        : itemId(itemId), title(title), type(type), loan(loan), num_copy(num_copy), fee(fee), genre(genre)
    {}
    ~Item() {}
    string getItemId() { return this->itemId; }
    string getTitle() { return this->title; }
    string getType() { return this->type; }
    string getLoan() { return this->loan; }
    string getCopy() { return this->num_copy; }
    string getFee() { return this->fee; }
    string getGenre() { return this->genre; }
};

Answer 1

你的问题是你的访问器不是return字符串&，而是一个不能作为字符串&传递的字符串的新副本。

    string& getItemId() { return itemId; }
    string& getTitle() { return title; }
    string& getType() { return type; }
    string& getLoan() { return loan; }
    string& getCopy() { return num_copy; }
    string& getFee() { return fee; }
    string& getGenre() { return genre; }

最重要的是，不要使用 using namespace std，在构造函数中使用 std::move，不要使用 exit 但抛出异常...

没有重载函数的实例匹配参数列表，参数类型是：(std::ifstream, std::string, char)

No instance of overloaded function matches the argument list, argument types are: (std::ifstream, std::string, char)

c++

getline