子类拷贝构造函数的问题【拜托各位看下】

[mabo321]

class Prototype
{
public:
	Prototype(string st)
	{
		str = st;
	}
	string Get()
	{
		return str;
	}

	virtual Prototype * Clone()=0;
	virtual ~Prototype(){}
private:
	string str;
};


class ConcretePrototype1 : public Prototype
{
public:
	ConcretePrototype1(string st) : Prototype(st)
	{
	}
	ConcretePrototype1(const ConcretePrototype1 & proto)  // 就这块，提示父类Prototype没有默认构造。
	{
		member = proto.member;
		cout << " ConcretePrototype1 Copy  ... " <<endl;
	}
	Prototype * Clone()
	{
		member = new ConcretePrototype1(*this);
		return member;
	}

	~ConcretePrototype1()
	{}
private:
	ConcretePrototype1 * member;
};

如果我在 父类Prototype中加一个默认构造 ，那么 Clone()函数拷贝出来的对象 的Get()值是空的啊……（可是我想的是 连父类的属性一起拷贝啊）

小弟我应该怎么弄啊……各位大虾，拜托指点一二……不胜感激

[baihacker]

class Prototype
{
public:
Prototype(string st)
{
str = st;
}
string Get() const //const
{
return str;
}

virtual Prototype * Clone()=0;
virtual ~Prototype(){}
private:
string str;
};


class ConcretePrototype1 : public Prototype
{
public:
ConcretePrototype1(string st) : Prototype(st)
{
}
ConcretePrototype1(const ConcretePrototype1 & proto): Prototype( proto.Get()) //调用一下父类的 {
member = proto.member;
cout << " ConcretePrototype1 Copy ... " <<endl;
}
Prototype * Clone()
{
member = new ConcretePrototype1(*this);
return member;
}

~ConcretePrototype1()
{}
private:
ConcretePrototype1 * member;
};

[星羽]

class Prototype
{
public:
    Prototype(string st)
    {
        str = st;
    }
    string Get()
    {
        return str;
    }

    virtual Prototype * Clone()=0;
    virtual ~Prototype(){}
protected:
    string str;
};


class ConcretePrototype1 : public Prototype
{
public:
    ConcretePrototype1(string st) : Prototype(st)
    {
    }
    ConcretePrototype1(const ConcretePrototype1 & proto)  // 就这块，提示父类Prototype没有默认构造。
        : Prototype(proto.str)
    {
        member = proto.member;
        cout << " ConcretePrototype1 Copy  ... " <<endl;
    }
    Prototype * Clone()
    {
        member = new ConcretePrototype1(*this);
        return member;
    }

    ~ConcretePrototype1()
    {}
private:
    ConcretePrototype1 * member;
};

[waizqfor]

[Quote=引用 1 楼 baihacker 的回复:]
class Prototype
{
public:
Prototype(string st)
{
str = st;
}
string Get() const //const
{
return str;
}

virtual Prototype * Clone()=0;
virtual ~Prototype(){}
private:
string str;
};


class ConcretePrototype1 : public Prototype
{
public:
ConcretePrototype1(string st) : Prototype(st)
{
} …
[/Quote]
UP

[oyljerry]

初始化列表，把str初始化你的父类

[xiaoyisnail]

#include <string>
#include <iostream>
using namespace std;

class Prototype
{
public:
    Prototype(string st)
    {
        str = st;
    }
    string Get()
    {
        return str;
    }

    virtual Prototype * Clone()=0;
    virtual ~Prototype(){}
private:
    string str;
};


class ConcretePrototype1 : public Prototype
{
public:
    ConcretePrototype1(string st) : Prototype(st)
    {
    }
    ConcretePrototype1(const ConcretePrototype1 & proto):Prototype("") //可以这样用空串来初始化
    {
        member = proto.member;
        cout << " ConcretePrototype1 Copy  ... " <<endl;
    }
    Prototype * Clone()
    {
        member = new ConcretePrototype1(*this);
        return member;
    }

    ~ConcretePrototype1()
    {}
private:
    ConcretePrototype1 * member;
};

[xiaoyisnail]

#include <string>
#include <iostream>
using namespace std;

class Prototype
{
public:
	Prototype():str(""){}//或者这样为父类提供一个默认构造函数
    Prototype(string st)
    {
        str = st;
    }
    string Get()
    {
        return str;
    }

    virtual Prototype * Clone()=0;
    virtual ~Prototype(){}
private:
    string str;
};


class ConcretePrototype1 : public Prototype
{
public:
    ConcretePrototype1(string st) : Prototype(st)
    {
    }
    ConcretePrototype1(const ConcretePrototype1 & proto)
    {
        member = proto.member;
        cout << " ConcretePrototype1 Copy  ... " <<endl;
    }
    Prototype * Clone()
    {
        member = new ConcretePrototype1(*this);
        return member;
    }

    ~ConcretePrototype1()
    {}
private:
    ConcretePrototype1 * member;
};

[mabo321]

class Prototype
{
public:
    Prototype(string st)
    {
        str = st;
    }
    string Get()
    {
        return str;
    }

    virtual Prototype * Clone()=0;
    virtual ~Prototype(){}
private:
    string str;
};


class ConcretePrototype1 : public Prototype
{
public:
    ConcretePrototype1(string st) : Prototype(st)
    {
    }
    ConcretePrototype1(ConcretePrototype1 & proto) : Prototype(proto.Get()) // 这样可以，我脑子唬住了0_o (星雨大哥的不能访问私有成员)
    {                                             
        member = proto.member;
        cout << " ConcretePrototype1 Copy  ... " <<endl;
    }
    Prototype * Clone()
    {
        member = new ConcretePrototype1(*this);
        return member;
    }

    ~ConcretePrototype1()
    {}
private:
    ConcretePrototype1 * member;
};

谢谢 各位……

[mabo321]

5，6楼的，也可以，
不过就是 没有 原始的Clone下来……

[mabo321]

再次感谢 各位…… 尤其是 飞雪 同志。。

飞雪同志是个好同志啊……