CMap，映射表类，也叫字典，一对一。适合用于频繁替换和查找的数据，由Key和Value组成，一般将Key作为唯一变量，通过Key即可找到Value。

//头文件#include 
     
      //定义,继承于CObject//template< class KEY, class ARG_KEY, class VALUE, class ARG_VALUE >class CMap : public CObject//KEY：Class of the object used as the key to the map.//ARG_KEY：Data type used for KEY arguments; usually a reference to KEY.//VALUE：Class of the object stored in the map.//ARG_VALUE：Data type used for VALUE arguments; usually a reference to VALUE.    CMap
      
        MyMap1;    CMap
       
         MyMap2;    //LPCTSTR也就是TCHAR*，也即是char*或者wchar*。    //添加也是设定值    MyMap1.SetAt(1,98.0);    MyMap2.SetAt(_T("张三"),1);    MyMap1[1] = 99.0;    //查找    double dTest = 0;    if (MyMap1.Lookup(1,dTest))    {        AfxMessageBox(_T("找到了"));        //此时dTest的值已经是99.0了    }    //获取个数    int nLength = MyMap2.GetCount();    //遍历    CString strKey = _T("");    int nValue = 0;    POSITION pos = MyMap2.GetStartPosition();    while(pos)    {        MyMap2.GetNextAssoc(pos,strKey,nValue);    }    //删除    MyMap1.RemoveKey(1);    //清空    if(!MyMap1.IsEmpty())//判定是否为空        MyMap1.RemoveAll(); //不会执行，前面已经删掉了    if (!MyMap2.IsEmpty())        MyMap2.RemoveAll();