inventory_referencer.cpp

来自「the source of dev_c++ most of them for 」· C++ 代码 · 共 51 行

// Inventory Referencer
// Demonstrates returning a reference

#include <iostream>
#include <string>
#include <vector>

using namespace std;

//returns a reference to a string
string& refToElement(vector<string>& inventory, int i); 

int main()
{
    vector<string> inventory;
    inventory.push_back("sword");
    inventory.push_back("armor");
    inventory.push_back("shield");

    //displays string that the returned reference refers to 
    cout << "Sending the returned reference to cout:\n";   
    cout << refToElement(inventory, 0) << "\n\n";

    //assigns one reference to another -- inexpensive assignment 
    cout << "Assigning the returned reference to another reference.\n";
    string& rStr = refToElement(inventory, 1); 
    cout << "Sending the new reference to cout:\n";
    cout << rStr << "\n\n";

    //copies a string object -- expensive assignment
    cout << "Assigning the returned reference to a string object.\n";
    string str = refToElement(inventory, 2);
    cout << "Sending the new string object to cout:\n";
    cout << str << "\n\n";
    
    //altering the string object through a returned reference
    cout << "Altering an object through a returned reference.\n";
    rStr = "Healing Potion";
    cout << "Sending the altered object to cout:\n";
    cout << inventory[1] << endl;

    return 0;
}

//returns a reference to a string
string& refToElement(vector<string>& vec, int i)
{
    return vec[i];
}