类的静态成员(外加 头文件.h和实现文件.cpp的用法)

静态成员变量最一般的作用就是对一些共享资源提供存取控制,减少全局变量的使用.

Student.h:

#include <iostream.h>
#include <string.h>

class Student
{
private:
int number;
char *name;
float score;
static int count;
static float sum;
public:
Student(int number1,char *name1,float score1);
~Student();
void modify(float score1)
{
score = score1;
}
void print();
};

Student.cpp:
#include <string>
#include "Student.h"
#include <iostream>
using namespace std;

Student::Student(int number1,char *name1,float score1)
{
number = number1;
name = new char[strlen(name1)+1];
strcpy(name,name1);
score = score1;
count++;
sum+=score;
}

Student::~Student()
{
delete []name;
count--;
}

void Student::print()
{
std::cout<<"number:"<<number<<" name:"<<name<<" score:"<<score<<" count:"<<count<<endl;
}

int Student::count=0;
float Student::sum=0;

main.cpp:
#include "Student.h"
#include <iostream>
using namespace std;

int main()
{
Student stu1(1,"Bill",77);
stu1.print();

Student stu2(2,"Adam",88);
stu2.print();

Student stu3(3,"David",99);
stu3.print();

return 0;
}源码布局:


程序执行: