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在C ++中的类初始化器中初始化一个const数组

更新时间:2022-10-15 15:50:06

像其他人说的,ISO C ++不支持。但你可以解决它。只需使用std :: vector代替。

  int * a = new int [N] 
//填充

类C {
const std :: vector< int> v;
public:
C():v(a,a + N){}
};


I have the following class in C++:

class a {
    const int b[2];
    // other stuff follows

    // and here's the constructor
    a(void);
}

The question is, how do I initialize b in the initialization list, given that I can't initialize it inside the body of the function of the constructor, because b is const?

This doesn't work:

a::a(void) : 
    b([2,3])
{
     // other initialization stuff
}

Edit: The case in point is when I can have different values for b for different instances, but the values are known to be constant for the lifetime of the instance.

Like the others said, ISO C++ doesn't support that. But you can workaround it. Just use std::vector instead.

int* a = new int[N];
// fill a

class C {
  const std::vector<int> v;
public:
  C():v(a, a+N) {}
};