Struct:初始化器错误

Question

对于下面的代码，我得到了以下消息。它们是：

1>c:\users\s1\desktop\c++folder\pr5\pr5\pr5.cpp(11): error C2078: too many initializers
1>c:\users\s1\desktop\c++folder\pr5\pr5\pr5.cpp(13): error C2143: syntax error : missing ';' before '.'
1>c:\users\s1\desktop\c++folder\pr5\pr5\pr5.cpp(13): error C2373: 'newBean' : redefinition; different type modifiers
1>c:\users\s1\desktop\c++folder\pr5\pr5\pr5.cpp(12) : see declaration of 'newBean'
1>c:\users\s1\desktop\c++folder\pr5\pr5\pr5.cpp(14): error C2143: syntax error : missing ';' before '.'

这是下面的代码。我怎么才能修复代码呢？我已将结构成员设置为静态常量。

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

 struct coffeeBean
{
    static const string name;
    static const string country;
    static const int strength;
};
 coffeeBean myBean = {"yes", "hello", 10 };
 coffeeBean newBean;
 const string newBean.name = "Flora";
 const string newBean.country = "Mexico";
 const int newBean.strength = 9; 

int main( int argc, char ** argv ) {

 cout << "Coffee bean " + newBean.name + " is from " + newBean.country << endl;
 system("pause");
 return 0;
}

Answer 1

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

struct coffeeBean
{
    string name;                     
    string country;                         
    int strength;
};
 coffeeBean myBean = {"yes", "hello", 10 };
 coffeeBean newBean;

int main( int argc, char ** argv ) {

newBean.name = "Flora";
newBean.country = "Mexico";
newBean.strength = 9; 
 cout << "Coffee bean " + newBean.name + " is from " + newBean.country << endl;
 system("pause");
 return 0;
}

有几件事：

如果要初始化变量，请不要在全局范围内执行此操作。

如果要赋值给变量，请不要在其上声明类型：

const string newBean.name = "Flora";//declare new variable, or assign to newBean.name ??

就像这样分配给它：

newBean.name = "Flora";

如果你想拥有一个类的所有实例都通用的变量，那么可以使用static。如果你想要一个变量，它在不同的实例中是不同的(通常使用OOP)，不要声明const。

最后，声明常量，如果你不打算改变的值。

Answer 2

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

struct coffeeBean
{
    string name; // can't be static because you want more 
                 // than one coffeeBean to have different values
    string country; // can't be const either because newBean 
                    // will default-construct and then assign to the members
    int strength;
};
 coffeeBean myBean = {"yes", "hello", 10 };
 coffeeBean newBean;
 newBean.name = "Flora";
 newBean.country = "Mexico";
 newBean.strength = 9; 

int main( int argc, char ** argv ) {

 cout << "Coffee bean " + newBean.name + " is from " + newBean.country << endl;
 system("pause");
 return 0;
}

已修复。请参见注释。