Question

下面我已经包含了我的h文件，我的问题是编译器不喜欢我的简单异常类的构造函数和初始化列表。它也是string is undeclared identifier，即使我在h文件的顶部有#include <string>。你看到我做错了吗？有关进一步说明，这是我在Windows上集成到wxWidgets GUI应用程序中的域类之一。

谢谢！

time.h中

#pragma once

#include <string>
#include <iostream>

// global constants for use in calculation
const int HOURS_TO_MINUTES = 60;
const int MINUTES_TO_HOURS = 100;

class Time
{
public:
   // default Time class constructor
   // initializes all vars to default values
   Time(void);
   // ComputeEndTime computes the new delivery end time
   // params - none
   // preconditions - vars will be error-free
   // postconditions - the correct end time will be returned as an int
   // returns an int
   int ComputeEndTime();
   // GetStartTime is the getter for var startTime
   // params - none
   // returns an int
   int GetStartTime() { return startTime; }
   // GetEndTime is the getter for var endTime
   // params - none
   // returns an int
   int GetEndTime() { return endTime; }
   // GetTimeDiff is the getter for var timeDifference
   // params - none
   // returns a double
   double GetTimeDiff() { return timeDifference; }
   // SetStartTime is the setter for var startTime
   // params - an int
   // returns void
   void SetStartTime(int s) { startTime = s; }
   // SetEndTime is the setter for var endTime
   // params - an int
   // returns void
   void SetEndTime(int e) { endTime = e; }
   // SetTimeDiff is the setter for var timeDifference
   // params - a double
   // returns void
   void SetTimeDiff(double t) { timeDifference = t; }
   // destructor for Time class
   ~Time(void);
private:
   int startTime;
   int endTime;
   double timeDifference;
};

class HourOutOfRangeException
{
public:
   // param constructor
   // initializes message to passed paramater
   // preconditions - param will be a string
   // postconditions - message will be initialized
   // params a string
   // no return type
   HourOutOfRangeException(string pMessage) : message(pMessage) {}
   // GetMessage is getter for var message
   // params none
   // preconditions - none
   // postconditions - none
   // returns string
   string GetMessage() { return message; }
   // destructor
   ~HourOutOfRangeException() {}
private:
   string message;
};

class MinuteOutOfRangeException
{
public:
   // param constructor
   // initializes message to passed paramater
   // preconditions - param will be a string
   // postconditions - message will be initialized
   // params a string
   // no return type
   MinuteOutOfRangeException(string pMessage) : message(pMessage) {}
   // GetMessage is getter for var message
   // params none
   // preconditions - none
   // postconditions - none
   // returns string
   string GetMessage() { return message; }
   // destructor
   ~MinuteOutOfRangeException() {}
private:
   string message;
};

class PercentageOutOfRangeException
{
public:
   // param constructor
   // initializes message to passed paramater
   // preconditions - param will be a string
   // postconditions - message will be initialized
   // params a string
   // no return type
   PercentageOutOfRangeException(string pMessage) : message(pMessage) {}
   // GetMessage is getter for var message
   // params none
   // preconditions - none
   // postconditions - none
   // returns string
   string GetMessage() { return message; }
   // destructor
   ~PercentageOutOfRangeException() {}
private:
   string message;
};

class StartEndException
{
public:
   // param constructor
   // initializes message to passed paramater
   // preconditions - param will be a string
   // postconditions - message will be initialized
   // params a string
   // no return type
   StartEndException(string pMessage) : message(pMessage) {}
   // GetMessage is getter for var message
   // params none
   // preconditions - none
   // postconditions - none
   // returns string
   string GetMessage() { return message; }
   // destructor
   ~StartEndException() {}
private:
   string message;
};

Answer 1

string位于名称空间std中，因此您需要对其进行限定：std::string。初始化列表与问题无关。

在不相关的说明中，您可能会考虑让您的异常类派生自标准库异常之一，例如std::runtime_error。

带初始化列表的简单构造函数？

time.h中

1 个答案: