#include "stdafx.h" 
    #include <iostream> 
    using namespace std; 
    class B 
    { 
    public: 
        B():data(0)    //默認構造函數 
        {  
            cout << "Default constructor is called." << endl; 
        } 
        B(int i):data(i) //帶參數的構造函數 
        { 
            cout << "Constructor is called." << data << endl; 
        } 
        B(B &b)   // 復制（拷貝）構造函數 
        { 
            data = b.data; cout << "Copy Constructor is called." << data << endl; 
        } 
        B& operator = (const B &b) //賦值運算符的重載 
        { 
            this->data = b.data; 
            cout << "The operator /"= /" is called." << data << endl; 
            return *this; 
        } 
        ~B() //析構函數 
        { 
            cout << "Destructor is called. " << data << endl; 
        } 
    private: 
        int data; 
    }; 

    //函數，參數是一個B類型對象，返回值也是一個B類型的對象 
    B fun(B b) 
    { 
        return b; 
    } 

    //測試函數 
    int _tmain(int argc, _TCHAR* argv[]) 
    { 
        fun(1); 
        cout << endl; 

        B t1 = fun(2); 
        cout << endl; 

        B t2; 
        t2 = fun(3); 

        return 0; 
    } 

    Constructor is called.1             //用1構造參數b    
    Copy Constructor is called.1      //用b拷貝構造一個臨時對象，因為此時沒有對象來接受fun的返回值    
    Destructor is called. 1            //參數b被析構    
    Destructor is called. 1             //臨時對象被析構 
    Constructor is called.2                  //用2構造參數b       
    Copy Constructor is called.2           //用b拷貝構造t1，此時調用的是拷貝構造函數    
    Destructor is called. 2                  //參數b被析構 
    Default constructor is called.             //調用默認的構造函數構造t2       
    Constructor is called.3                       //用3構造參數b       
    Copy Constructor is called.3             //用b拷貝構造一個臨時對象       
    Destructor is called. 3                        //參數b被析構       
    The operator "= " is called.3              //調用=操作符初始化t2，此時調用的是賦值操作符    
    Destructor is called. 3                         //臨時對象被析構       
    Destructor is called. 3                         //t2被析構       
    Destructor is called. 2                         //t1被析構       
    請按任意鍵繼續. . .