Why the use of const in a method with no parameters?

This question already has an answer here:

Meaning of “const” last in a C++ method declaration? 7 answers

What is meant with “const” at end of function declaration? [duplicate] 6 answers

---

Banning the modification of members is not the only reason to qualify a member function as const . Whether you want to modify members or not, you can only call a member function on an object through a const context if the member function is marked const :

#include <iostream>
#include <string>

struct List
{
   std::string reqClubName()
   {
      return m_Club;
   }

private:
   std::string m_Club;
};

int main()
{
   const List l;
   std::cout << l.reqClubName();
   // ^ illegal: `l` is `const` but, `List::reqClubName` is not
}

Neither the language nor the compiler care that reqClubName doesn't try to modify the object anyway; your program will not compile.

Because of this, a const suffix should be your default approach unless you do need to modify a data member.

---

成员函数后的const表示该函数不会修改它所属的类中的成员数据。

链接地址: http://www.djcxy.com/p/40436.html

上一篇: 这是什么意思const类型和方法

下一篇: 为什么在没有参数的方法中使用const？