//============================================================================
// Name : CppLab.cpp
// Author : sodino
// Version :
// Copyright : Your copyright notice
// Description : Hello World in C++, Ansi-style
//============================================================================
#include <iostream>
#include <string>
using namespace std;
struct Student{
string name;
};
int main() {
void print(Student);
void print_point(Student *);
void print_reference(Student &);
struct Student stu = {"Yao ming"};
cout << "main &stu=" << &stu << endl << endl;
print(stu);
cout << "after print() name=" << stu.name << " no changed."<< endl << endl;
print_point(&stu);
cout << "after print_point() name=" << stu.name << " has been modified." << endl << endl;
print_reference(stu);
cout << "after print_reference() name=" << stu.name << " has been modified." << endl;
return 0;
}
void print(Student stu) {
// 实参转形参,会消耗额外的时间。print_reference()则效率高许多。
cout << "print() stu address=" << &stu << " is different."<< endl; // 形参stu与函数体外的stu是两个不同的对象!!
stu.name = "new.name"; // 这里的赋值并不会改变函数体外stu的name
cout << "print() set new name=" << stu.name << endl;
}
void print_point(Student * stu) {
stu->name = "new.point.name";
cout << "print_point() set new name=" << stu->name << endl;
}
void print_reference(Student &stu) {
stu.name = "new.reference.name";
cout << "set new name=" << stu.name << endl;
}
main &stu=0x7fff5eabfbc8 print() stu address=0x7fff5eabfba0 is different. print() set new name=new.name after print() name=Yao ming no changed. print_point() set new name=new.point.name after print_point() name=new.point.name has been modified. set new name=new.reference.name after print_reference() name=new.reference.name has been modified.
原文:http://blog.csdn.net/sodino/article/details/41559787