C++ 构造函数错误：需要标识符？
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Error at constructor : Expected an identifier?
提问by Abd Al Rahman Hamdan
I am working with a bunch of classes with composition and I keep getting this error (Expected an identifier) when I try to implement the constructor , here the class header:
我正在处理一堆具有组合的类，当我尝试实现构造函数时，我不断收到此错误（预期的标识符），这里是类头：
#ifndef STUDENT_H_
#define STUDENT_H_
#include "University.h"
class Student {
public:
Student(); // constructor
friend ostream & operator<<(ostream &, Student &); // print the student data
friend istream & operator>>(istream &, Student &); // to read student data
private:
const int id;
string name;
int marks[5];
Date admissionDate; // Composition
University university; // Composition
};
#endif
what do I need to do to solve this error ?
我需要做什么来解决这个错误？
here's the cpp but I still did not implement the other io functions because I want to solve that error first..
这是 cpp，但我仍然没有实现其他 io 函数，因为我想先解决那个错误..
#include "Student.h"
Student::Student(){}
ostream & operator<<(ostream &, Student &){}
istream & operator>>(istream &, Student &){}
回答by Vlad from Moscow
Your constructor should be defined the following way
您的构造函数应按以下方式定义
Student::Student() { /* some code */ }
回答by A.E. Drew
Since a Studenthas a const int idmember, you need to initialize it in the constructor's
initialization list. E.g.:
由于 aStudent有一个const int id成员，您需要在构造函数的初始化列表中对其进行初始化。例如：
Student::Student() : id(0)
{ }
