c++ error C2512:沒有合適的默認構造函數可用

這是我最近學習c++過程中遇到的一個問題，同時也說明了自定義類的使用，這里借用別人的例子來說明一下這個問題。

 

#include "stdafx.h"
using namespace std;

/* --- --- --- --- --- --- --- 武器類 --- --- --- --- --- --- */
class Weapon
{
private:
    string name;
    int power;
public:
    void Show();
    //Weapon(){};
    Weapon(string name,int power);
};

Weapon::Weapon(string name, int power)
{
    this->name = name;
    this->power = power;
};

void Weapon::Show()
{
    cout<<"武器名："<<this->name<<"威力值："<<this->power<<endl;
};


/* --- --- --- --- --- --- --- 角色類 --- --- --- --- --- --- */

class Actor
{
private:
    string name;
    bool gender;
    Weapon weapon;
public:
    Actor(string name, bool gender);
    void Say();
    void Say(string message);
    void SetWeapon(Weapon &weapon)
    {
        this->weapon = weapon;
    }
};

Actor::Actor(string name, bool gender)
{
    this->gender = gender;
    this->name = name;
}

void Actor::Say()
{
    cout<<"我乃"<<this->name<<"是也..."<<endl;
};

void Actor::Say(string message)
{
    cout<<this->name<<"："<<message<<endl;
};

 

 

　　

注釋掉Weapon的void構造函數會提示error C2512: “Weapon”: 沒有合適的默認構造函數可用。

 

1、由於你在Weapon中定義了其他構造函數，那么，編譯器不會為你創建默認構造函數；然而，你在Actor的構造函數中沒有調用Weapon的構造函數，那么，編譯器會調用Weapon的默認構造函數，然而，卻沒有定義，所以，產生了“error C2512: “Weapon”: 沒有合適的默認構造函數可用”錯誤！