求助大神，C++报错 LNK2001

[. 水怪]

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

class Dishes
{
public:
string Name;//餐品名
int Price;//单价
friend istream &operator>>(istream &input, Dishes &D)
{
input >> D.Name >> D.Price;
return input;
}
friend ostream &operator<<(ostream &output, Dishes &D)
{
output << D.Name << D.Price;
return output;
}
};
class Order_document
{
private:
Dishes _Dish[7];//餐品信息
int Number[7];//份数
int Amount_Price;//总价
public:
static Dishes dish[7];
Order_document()
{
}
void Read_menu()
{
ifstream file1("C:\\Users\\60957\\Desktop\\19170130\\data.txt");
if (!file1)
{
cout << "无法读入菜单" << endl;
}
else
{
for (int i = 0;i<7;i++)
{
file1 >> dish[i];
}
file1.close();
for (int i = 0;i<7;i++)
{
cout << dish[i] << endl;
}
}
}
void Order()
{
int i;
for (i = 0;i<7;i++)
{
cout << dish[i] << endl;
}
for (i=0;;i++)
{
int No = 0;
int Num = 0;
cout << "请输入餐品序号(如结束点单请输入0):" << endl;
cin >> No;
if (No == 0)
break;
_Dish[i].Name = dish[No + 1].Name;
cout << "请输入" << dish[No + 1].Name << "的份数:" << endl;
cin >> Num;
Number[i] = Num;
Amount_Price += (dish[No + 1].Price*Num);/////////////////////
}
cout << "------------------------------" << endl;
cout << "您的菜单为:" << endl;
for (int m = 0;m < i;m++)
{
cout << _Dish[i].Name << " " << Number[i] << "份" << endl;
}
}
};
class Queue
{
private:
Order_document customer;//顾客单据
int No;//单号
public:

};
int main()
{
Order_document order;
order.Read_menu();

Order_document customer1;
customer1.Order();
}

[sevancheng]

static Dishes dish[7]; 没初始化

[蠓虫带着秤砣飞]

楼上的说法正确，我改了一下，只管编译通过。

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

class Dishes
{
public:
	string Name;//餐品名
	int Price;//单价
	friend istream &operator>>(istream &input, Dishes &D)
	{
		input >> D.Name >> D.Price;
		return input;
	}
	friend ostream &operator<<(ostream &output, Dishes &D)
	{
		output << D.Name << D.Price;
		return output;
	}
};

class Order_document
{
private:
	Dishes _Dish[7];//餐品信息
	int Number[7];//份数
	int Amount_Price;//总价
public:
	static Dishes dish[7];
	Order_document()
	{

	}
	void Read_menu()
	{
		ifstream file1("C:\\Users\\60957\\Desktop\\19170130\\data.txt");
		if (!file1)
		{
			cout << "无法读入菜单" << endl;
		}
		else
		{
			for (int i = 0;i<7;i++)
			{
				file1 >> dish[i];
			}
			file1.close();
			for (int i = 0;i<7;i++)
			{
				cout << dish[i] << endl;
			}
		}
	}
	void Order()
	{
		int i;
		for (i = 0;i<7;i++)
		{
			cout << dish[i] << endl;
		}
		for (i=0;;i++)
		{
			int No = 0;
			int Num = 0;
			cout << "请输入餐品序号(如结束点单请输入0):" << endl;
			cin >> No;
			if (No == 0)
				break;
			_Dish[i].Name = dish[No + 1].Name;
			cout << "请输入" << dish[No + 1].Name << "的份数:" << endl;
			cin >> Num;
			Number[i] = Num;
			Amount_Price += (dish[No + 1].Price*Num);/////////////////////
		}
		cout << "------------------------------" << endl;
		cout << "您的菜单为:" << endl;
		for (int m = 0;m < i;m++)
		{
			cout << _Dish[i].Name << " " << Number[i] << "份" << endl;
		}
	}
};

Dishes Order_document::dish[7] = {0};

//Order_document::dish[0].Name="aaa";Order_document::dish[0].Price=1;
//Order_document::dish[1].Name="bbb";Order_document::dish[1].Price=2;
//Order_document::dish[2].Name="ccc";Order_document::dish[2].Price=3;
//Order_document::dish[3].Name="ddd";Order_document::dish[3].Price=4;
//Order_document::dish[4].Name="eee";Order_document::dish[4].Price=5;
//Order_document::dish[5].Name="fff";Order_document::dish[5].Price=6;
//Order_document::dish[6].Name="ggg";Order_document::dish[6].Price=7;

class Queue
{
private:
	Order_document customer;//顾客单据
	int No;//单号
public:

};
int main()
{
	Order_document order;
	order.Read_menu();

	Order_document customer1;
	customer1.Order();
}