C ++ typedef，map，iterator

Question

任何人都可以帮我解决迭代器问题吗？我有这样的事情：

class SomeClass{

public:
    //Constructor assigns to m_RefPtr a new t_Records
    //Destructor deletes m_RefPtr or decreases m_RefCnt
    //Copy Constructor assigns m_RefPtr to new obj, increases m_RefCnt
    bool Search(const string &);

private:
    //Some private variables

    struct t_Records{ //For reference counting

        int m_RefCnt; //Reference counter

        typedef vector<int> m_Vec;
        typedef map<string, m_Vec> m_Map;
        m_Map m_RecMap;

        t_Records(void){
            m_RefCnt = 1;
        }

    };

    t_Records * m_RefPtr;

};

//Searchs through the map of m_RefPtr, returns true if found
bool SomeClass::Search(const string & keyword){

    //How to create and use an iterator of m_Map???

    return true;

}

正如我所提到的，我在构造之外创建（定义）map迭代器时遇到了麻烦。地图是初始化的，包含一些记录。谢谢你的回复。

Answer 1

像这样：

// assuming m_RefPtr is properly initialized:
t_Records::m_Map::iterator it = m_RefPtr->m_RecMap.begin();
++it; // etc.

顺便说一下，m_Map是一个类型的错误名称。按照惯例，前缀为m_的名称用于数据成员。

Answer 2

您可以像这样迭代

for (m_Map::iterator it = m_RecMap.begin(); it != m_RecMap.end(); ++it)
{
    // do stuff with *it
}

甚至更容易

for (auto it = m_RecMap.begin(); it != m_RecMap.end(); ++it)
{
    // do stuff with *it
}