错误的类型重载++运算符

Question

我尝试在c ++中结合模板构建一个双重连接的列表。

如果我尝试编译Programm，Visual Studio会抛出一个

  

C2676错误：二进制运算符＆＃34; ++＆＃34;：Interator＆＃34;没有定义或   不会将此运算符转换为可用类型

为什么这不起作用？如果我添加另一个方法来执行相同的操作，如我的重载增量器，它工作正常，但如果我重载增量器，它会抛出我的错误。

这里有一些代码：

我的NodeElement类：

template<typename T>
class Nodeelement
{
public:
    Nodeelement(T data)
    {
        this->data = data;
        pNext = NULL;
    }
    Nodeelement *pPrev;
    Nodeelement *pNext;
    T data;
};

然后是我的迭代课：

template<typename T>
class Iterator
{
public:
    Nodeelement<T> *itr;
    Iterator(void) : itr(NULL) {}
    Iterator(Nodeelement<T>* le) : itr(le) {}

    void operator=(Nodeelement<T>* le)
    {
        itr = le;
    }

    bool operator!=(Nodeelement<T>* le)
    {
        if (NULL != itr && itr != le)
            return true;
        else
            return false;
    }

    void operator++()
    {
        if (itr != NULL)
            itr = itr->pNext;
    }

    void operator--()
    {
        if (itr != NULL)
            itr = itr->pPrev;
    }

    T& getData(void)
    {
        return itr->data;
    }
};

然后我的Node类：

template<typename T>
class Node
{
private:
    Nodeelement<T>* pFirst;
    Nodeelement<T>* pLast;
public:
    Node<T>::Node(void) { pFirst = pLast = NULL;}
    Node<T>::~Node() { removeEntry(); }
    void Node<T>::addEntry(T data)
    {
        Nodeelement<T> *newNodeElement = new Nodeelement<T>(data);
        if (isEmpty())
            pLast = pFirst = newNodeElement;
        else
        {
            pLast->pNext = newNodeElement;
            newNodeElement->pPrev = pLast;
            pLast = newNodeElement;
        }
    }
    bool isEmpty(void) { return (pFirst == NULL) ? true : false; }
    void removeEntry(void)
    {
        if (isEmpty())
            return;

        while (pFirst->pNext != NULL)
        {
            Nodeelement<T> *pNow = pLast->pPrev;
            pNow->pNext = NULL;
            delete pLast;
            pLast = pNow;
        }
        delete pFirst;
        pFirst = NULL;
    };
    void removeEntry(Iterator<T>& it)
    {
        if (pFirst->pNext == NULL)
        {
            delete pFirst;
            pFirst = pNext = NULL;
        }
        else if (it == pFirst)
        {
            pFirst = pFirst->pNext;
            delete pFirst->pPrev;
            pFirst->pPrev = NULL;
        }
        else if (it == pLast)
        {
            pLast = pLast->pPrev;

            delete pLast->pNext;
            pLast->pNext = NULL;
        }
        else
        {
            it.itr->pPrev->pNext = it.itr->pNext;
            it.iter->pNext->pPrev = it.iter->pPrev;
            delete it.itr;
        }
    };

    Nodeelement<T>* start(void) { return pFirst; }
    Nodeelement<T>* postpLast(void)
    {
        if (pLast == NULL)
            return NULL;
        else
            return pLast->pNext;
    }
};

和main.cpp文件：

#include "Node.h"
#include <string>
#include <conio.h>
struct Films
{
    std::string titel;
    unsigned int year;
    int genre;
};


void main(void)
{
    Films film, film1, film2;
    film.titel = "Stargate";
    film.year = 2005;
    film.genre = 1;

    film1.titel = "V";
    film1.year = 2009;
    film1.genre = 1;

    film2.titel = "Avatar";
    film2.year = 2009;
    film2.genre = 2;

    Node<Films> films;
    films.addEntry(film);
    films.addEntry(film1);
    films.addEntry(film2);

    Iterator<Films> itr;

    for (itr = films.start(); itr != films.postpLast(); itr++)
    {
        std::cout << "Film: " << itr.getData().titel.c_str() << std::endl;
    }

    _getch();
}

（数据只是用于可视化目的的虚拟数据）

我可以添加一个方法来处理递增/递减，但重载递增运算符对我来说看起来更干净（更合乎逻辑）

我希望我的问题很清楚