Question

在下面的代码段1和代码段2中给出了两个类定义，您能告诉我为什么我收到第3个代码段中显示的编译错误，我该如何解决它们？它看起来子类无法访问基类中的非虚拟公共方法（请参阅第二个代码片段中标记为第197行的子类中的方法getVipAddress）。我是C ++领域的新手，所以如果您碰巧看到代码块中需要任何其他改进，我将不胜感激。

SNIPPET 1（基础和子类）

// BASE CLASS

class BaseEntity
{
 public:
BaseEntity(): mUUID(""), mName("") {}
BaseEntity(std::string &uuid, std::string &name): mUUID(uuid), mName(name) { }

BaseEntity (const BaseEntity &copyin)
{
    this->mUUID = copyin.mUUID.c_str();
    this->mName = copyin.mName.c_str();
}

BaseEntity operator = (const BaseEntity &rhs)
{
    this->mUUID = rhs.mUUID.c_str();
    this->mName = rhs.mName.c_str();

    return *this;
}

~BaseEntity() { };

void setUUID(std::string uuid) { mUUID = uuid; }
void setName(std::string name) { mName = name; }

              /*LINE 89 is the following*/
const std::string &getUUID() const { return mUUID; }
const std::string &getName() const { return mName; }

  private:
std::string mUUID;
std::string mName;

};

// SUBCLASS

class VipAddressSet : BaseEntity
{
  public:
    VipAddressSet() : BaseEntity() { }
    VipAddressSet(std::string &uuid, std::string &name) : BaseEntity(uuid, name) { }

    VipAddressSet(const VipAddressSet &copyin)
    {
            setUUID(copyin.getUUID());
            setName(copyin.getName());

                std::vector<VipAddressEntity>::const_iterator iter;
            for( iter = copyin.mVipAddressList.begin(); iter !=  copyin.mVipAddressList.end(); iter++ )
            {

                addVipAddress(*iter);
            }
     }

     VipAddressSet operator = (const VipAddressSet &rhs)
     {
          setUUID(rhs.getUUID());
          setName(rhs.getName());

              std::vector<VipAddressEntity>::const_iterator iter;
          for( iter = rhs.mVipAddressList.begin(); iter != rhs.mVipAddressList.end(); iter++ )
              {
            addVipAddress(*iter);
          }

          return *this;
         }

     int getVipAddress(std::string &uuid, VipAddressEntity **ptr )
     {
        std::vector<VipAddressEntity>::const_iterator iter;
        for( iter = mVipAddressList.begin(); iter != mVipAddressList.end();  iter++ )
        {
   **/*~~~~ LINE 197 is the following ~~~~*/**
            if(iter->getUUID() == uuid)
            {
                **ptr = *iter;
                return 1;
            }
        }

        return 0;
     }


     const std::vector<VipAddressEntity>& getVipAddressList() const { return mVipAddressList; }


    private:
      std::vector<VipAddressEntity> mVipAddressList;

      void addVipAddress(const VipAddressEntity &entity)
      {
       mVipAddressList.push_back(entity);
      }

     };

汇编输出

  $ g++ -g -c -std=c++11 -Wall Entity.hpp
  Entity.hpp: In member function ‘int  ECLBCP::VipAddressSet::getVipAddress(std::string&, ECLBCP::VipAddressEntity**)’:
  Entity.hpp:89:21: error: ‘const string& ECLBCP::BaseEntity::getUUID() const’ is inaccessible
  Entity.hpp:197:24: error: within this context
  Entity.hpp:197:24: error: ‘ECLBCP::BaseEntity’ is not an accessible base of ‘const   ECLBCP::VipAddressEntity’

Answer 1

类的默认继承是私有的。将您的声明更改为

class VipAddressSet : public BaseEntity

Answer 2

那是因为你必须使用public modifier

继承它

class VipAddressSet : public BaseEntity

Answer 3

我猜你是继承private。尝试

 class VipAddressSet : public BaseEntity

否则该方法将不可见。

子类无法访问C ++公共非虚基类方法

3 个答案: