我对完成这个程序有点怀疑
评估要求我们根据下面提供的信息，实现RockConcert和TicketHolder类。 TicketHolder类代表支付特定音乐会入场费的人。这个TicketHolder类应该跟踪它的成本和座位所在的位置。
我已经构建了大部分代码，给出了提供的驱动程序，但我对如何编写方法RockConcert :: sellTicket和RockConcert :: getTicket
非常感到困惑以下是代码，
非常感谢！
TicketHolder.h
#ifndef TicketHolder_h
#define TicketHolder_h
#include <string>
#include <iostream>
using namespace std;
class TicketHolder {
public:
TicketHolder();
TicketHolder( std::string seat, double cost );
std::string getSeat() const;
double getCost() const;
friend std::ostream& operator<< (std::ostream& os, const TicketHolder & t);
private:
std::string my_Seat;
double my_Cost;
};
#endif
TicketHolder.cpp
#include "TicketHolder.h"
TicketHolder::TicketHolder(){
}
TicketHolder::TicketHolder( std::string seat, double cost ){
my_Seat = seat;
my_Cost = cost;
}
std::string TicketHolder::getSeat() const{
return (my_Seat);
}
double TicketHolder::getCost() const{
return (my_Cost);
}
std::ostream& operator<< (std::ostream& os, const TicketHolder & t){
return os;
}
RockConcert.h
#ifndef RockConcert_h
#define RockConcert_h
#include <string>
#include <iostream>
#include <stdexcept>
#include "TicketHolder.h"
#include "SeatAlreadySold.h"
#include "SeatNotFound.h"
class RockConcert {
public:
public:
RockConcert( std::string date, std::string location );
void sellTicket( std::string seat, double cost ) throw (SeatAlreadySold);
TicketHolder getTicket( std::string seat ) throw (SeatNotFound);
double getProceeds( );
friend std::ostream& operator<< ( std::ostream& out, const RockConcert & r );
private:
TicketHolder myTickets[ 20 ];
int myNumberOfTicketsSeenSoFar;
std::string my_When;
std::string my_Where;
};
#endif
RockConcert.cpp
#include "RockConcert.h"
#include "TicketHolder.h"
RockConcert::RockConcert( std::string date, std::string location ) {
my_When = date;
my_Where = location;
}
void RockConcert::sellTicket( std::string seat, double cost ) throw (SeatAlreadySold){
}
TicketHolder RockConcert::getTicket( std::string seat ) throw(SeatNotFound) {
}
double RockConcert::getProceeds( ){
return (myNumberOfTicketsSeenSoFar);
}
std::ostream& operator<< ( std::ostream& out, const RockConcert & r ){
return out;
}
Driver.CPP
// driver
// function main
#include "TicketHolder.h"
#include "RockConcert.h"
#include <iostream>
#include <stdexcept>
int main(int argc, const char * argv[])
{
RockConcert megaDeath( "Sept 1", "Staples Center" );
megaDeath.sellTicket( "Row Q Seat 20", 120.00 );
megaDeath.sellTicket( "Row Q Seat 21", 120.00 );
megaDeath.sellTicket( "Row SSS Seat 12", 50.00 );
TicketHolder ticket = megaDeath.getTicket( "Row Q Seat 21" );
// Print out the concert and its tickets
std::cout << megaDeath << std::endl;
try {
megaDeath.sellTicket( "Row T Seat 30", 65.00 );
} catch( SeatAlreadySold sas ) {
std::cout << "An error occurred here for the reason:";
std::cout << sas.what(std::endl:endl;
}
// Print out the library and its book - notice the difference
std::cout << megaDeath << std::endl;
// Let's try to throw some errors...
try {
// can't sell a ticket that has already been sold
megaDeath.sellTicket( "Row Q Seat 21", 120.00 );
std::cout << "An error occurred here..." ;
} catch( SeatAlreadySold sas ) {
sas.what();
}
try {
// can't get a ticket that has not been sold
megaDeath.getTicket( "Row A Seat 1" );
std::cout << "An error occurred here..." ;
} catch( SeatNotFound snf ) {
snf.what();
}
}
答案 0 :(得分：1)
我不确定这里的问题究竟是什么，但我倾向于创建一个std::map映射一个票证ID（它可能是一个像“Row ## Seat ##”这样的字符串，如同只要你一致）到TicketHolder个实例。您的TicketHolder类（我认为更好地命名为Ticket）应该包含一个布尔“已售出”属性。
在getTicket()方法中，std::map中的简单查找就可以了，而且非常快。
您的sellTicket()方法应首先调用getTicket()，然后检查返回的故障单的“已售出”属性（如果已售出则抛出异常）。如果没有，请设置TicketHolder::sold = true。您还应该将票证成本添加到目前为止的累计收益中。
其他可能有用的一般规则：
std::string和其他复杂对象