错误"额外资格'学生::'对会员'学生'[-fpermissive]"

Question

我收到了一个错误extra qualification ‘student::’ on member ‘student’ [-fpermissive].
还有为什么name::name在构造函数中使用这种语法？

#include<iostream>
#include<string.h>
using namespace std;
class student
{
 private:
     int id;
     char name[30];
 public:
/*   void read()
     {
        cout<<"enter id"<<endl;
        cin>>id;
        cout<<"enter name"<<endl;
        cin>>name;
     }*/
     void show()
     {
        cout<<id<<name<<endl;
     }
     student::student()
     {
        id=0;
        strcpy(name,"undefine");
     }
};
main()
{
 student s1;
// s1.read();
 cout<<"showing data of s1"<<endl;
 s1.show();
// s2.read();
  //cout<<"showing data of s2"<<endl;
 //s2.show();
}

Answer 1

成员函数/构造函数/析构函数的类内定义不需要诸如的限定student::.

所以这段代码,

 student::student()
 {
    id=0;
    strcpy(name,"undefine");
 }

应该这样:

 student()
 {
    id=0;
    strcpy(name,"undefine");
 }

资格student::,如果你定义类的外部成员函数只需要,通常在.cpp文件.