c++ - 如何为我的类创建数组构造函数？

Question

我想创建一个类似于 int 数组构造函数的构造函数:int foo[3] = { 4, 5, 6 };

但我想这样使用它:

MyClass<3> foo = { 4, 5, 6 };

我的类(class)里有一个私有(private)的n大小的数组:

template<const int n=2>
class MyClass {

    public:

        // code...

    private:

        int numbers[n];

        // code...

};

Answer 1

您需要一个接受 std::initializer_list 的构造函数参数:

MyClass(std::initializer_list<int> l)
{
    ...if l.size() != n throw / exit / assert etc....
    std::copy(l.begin(), l.end(), &numbers[0]);
}

TemplateRex评论...

You might want to warn that such constructors are very greedy and can easily lead to unwanted behavior. E.g. MyClass should not have constructors taking a pair of ints.

...并且担心过度活跃的版主可能会删除它，所以这里相对安全。 :-)