c++ - Cpp 在不需要时询问默认构造函数

Question

我的代码:

#include "BaseProduct.h"

BaseProduct::BaseProduct(
    const ProductBaseType baseType,
    const int id,
    const int quantity,
    const Location location
    ) {
    _baseType = baseType;
    _id = id;
    _quantity = quantity;
    _location = location;
}

我得到的错误:

no default constructor exists for class "Location"

我知道 Location 没有任何默认构造函数，它的目的是...... 如果有任何相关性，我会使用 VSCode。

提前致谢!

Answer 1

您可能希望重写构造函数以使用初始化列表形式。否则，在您可以在构造函数主体中初始化它们之前，默认构造函数将用于您的成员:

• https://en.cppreference.com/w/cpp/language/initializer_list

引用上面链接的文档(强调我的):

Before the compound statement that forms the function body of the constructor begins executing, initialization of all direct bases, virtual bases, and non-static data members is finished. Member initializer list is the place where non-default initialization of these objects can be specified. For members that cannot be default-initialized, such as members of reference and const-qualified types, member initializers must be specified.

例子:

BaseProduct::BaseProduct(
    const ProductBaseType baseType,
    const int id,
    const int quantity,
    const Location location
    ) : _baseType(baseType), _id(id), _quantity(quantity), _location(location) { }