C++/CLI multiple errors - visual-c++

Question

I am getting multiple, confusing errors when building this school assignment and am hoping for some direction on what might be the problem. I wouldn't normally write it like this, but I put everything into one file as I try to debug this. Using Visual Studios Express 2012. I'm getting over 30 errors when I build, so I'm sure there is something fundamental that I am simply overlooking. Just a suggestion please, not looking for anyone to do my homework. Thanks
#include "stdafx.h"
#include <Windows.h>
#include <iostream>
#include "MessageDisplayClass.h"
#include "LogMessageClass.h"
#include "TimerEventArgs.h"
using namespace System;
ref class CustomTimerClass
{
private:
static bool stopFlag = false;
// create instance of TimerEventArgs
TimerEventArgs^ timerEvent;
public:
CustomTimerClass(void)
{
}
delegate void CustomTimerClass::TimerAlarmHandler(/*Object^ sender, TimerEventArgs^ args*/);
event CustomTimerClass::TimerAlarmHandler^ OnTimerAlarm;
property bool StopFlag
{
bool get(void)
{
return stopFlag;
}
void set(bool b)
{
stopFlag = b;
}
}
void run()
{
Sleep(1000);
raiseTimerAlarm();
}
void OnStart()
{
// create instances of DisplayMessageClass and LogMessageClass classes
DisplayMessageClass^ messageDisplayer = gcnew DisplayMessageClass(this);
LogMessageClass^ messageLogger = gcnew LogMessageClass(this);
// display and log messages concerning this event
messageDisplayer->displayMessage(this, timerEvent);
messageLogger->logMessage(this, timerEvent);
}
void raiseTimerAlarm()
{
// create instance of TimerEventArgs and get time of instance creation
timerEvent = gcnew TimerEventArgs();
String^ eventTime = timerEvent->EventTime;
// tie this instance of CustomTimerClass to OnTimerAlarm event and start event
this->OnTimerAlarm += gcnew TimerAlarmHandler(this, &CustomTimerClass::OnStart);
OnTimerAlarm();
}
};
ref class MainProgram
{
int main(array<System::String ^> ^args)
{
CustomTimerClass^ timerClass = gcnew CustomTimerClass();
DisplayMessageClass^ messageClass = gcnew DisplayMessageClass();
LogMessageClass^ logerClass = gcnew LogMessageClass();
timerClass->run();
return 0;
}
};

Answer 1

At the point you're trying to use the various classes, the compiler doesn't know about them yet. Move your main() function to the end of the file. Or better, split your class definitions in their own header files and then include them in your main source file.
There are other related problems too. For example, you're trying to use the TimerEventArgs class before the compiler knows about it. So you need to move the class definition up. This is why it's best to have each class in its own header file, and then include it where needed. Though it's not strictly unnecessary, if you declare/define everything in the correct order.

Answer 2

Other than wrong order of declarations, it looks like the problem is that the compiler doesn't recognize the ^ bit, which suggests you're not compiling as C++/CLI. Righ-click the project in Solution Explorer and go to Configuration Properties -> General, and make sure that Common Language Runtime Support is set to Common Language Runtime Support (/clr).

Answer 3

For the benefit of anyone else (other newbies): As it turns out, my suspicion that the problem lay in the fact that some of the classes were "#including" each other was the problem. Using forward declarations, combined with having to create a separate class altogether to act as a variable storage handler was the solution to my problem.
Here are the two classes that were giving me the biggest problem, corrected to function correctly:
/*
CustomTimerClass.h
*/
#include "StdAfx.h"
#include "LogMessageClass.h"
#include "MessageDisplayClass.h"
#include "TimerEventArgs.h"
#include "Variables.h"
//ref class MessageDisplayClass;
//ref class Variables;
using namespace System;
ref class CustomTimerClass
{
private:
static bool stopFlag = false;
// create instance of TimerEventArgs
TimerEventArgs^ timerEvent;
// create instance of MessageDisplayClass and LogMessageClass
MessageDisplayClass^ messageDisplayer;
LogMessageClass^ messageLogger;
Variables^ flagVariable;
public:
CustomTimerClass(void)
{
}
delegate void CustomTimerClass::TimerAlarmHandler();
event CustomTimerClass::TimerAlarmHandler^ OnTimerAlarm;
property bool StopFlag
{
bool get(void)
{
return stopFlag;
}
void set(bool b)
{
stopFlag = flagVariable->Flag;
}
}
void run()
{
Sleep(1000);
raiseTimerAlarm();
}
void OnStart()
{
// create instances of DisplayMessageClass and LogMessageClass classes
messageDisplayer = gcnew MessageDisplayClass(this, flagVariable);
messageLogger = gcnew LogMessageClass(this);
// display and log messages concerning this event
messageDisplayer->displayMessage(this, timerEvent);
messageLogger->logMessage(this, timerEvent);
}
void raiseTimerAlarm()
{
// create instance of TimerEventArgs and get time of instance creation
timerEvent = gcnew TimerEventArgs();
String^ eventTime = timerEvent->EventTime;
// tie this instance of CustomTimerClass to OnTimerAlarm event and start event
this->OnTimerAlarm += gcnew TimerAlarmHandler(this, &CustomTimerClass::OnStart);
OnTimerAlarm();
}
};
/*
MessageDisplayClass serves to display a message that
represents the time at which the TimerEventArgs class is
instantiated. This time is returned through a function
of TimerEventArgs class.
*/
#pragma once
#include "stdafx.h"
#include <iostream>
#include "TimerEventArgs.h"
#include "Variables.h"
using namespace System;
ref class CustomTimerClass; // FORWARD DECLARATION HERE CAN
// ONLY BE USED FOR REFERENCE. CANNOT
// BE USED WHEN METHODS OF THE CLASS
// ARE CALLED
ref class MessageDisplayClass
{
private:
CustomTimerClass^ customTimerRef;
// Variables CLASS CREATED SOLELY TO ACT AS GO-BETWEEN BETWEEN
// MessageDisplayClass and CustomTimerClass
Variables^ variableRef;
static int counter;
public:
// constructor
MessageDisplayClass(CustomTimerClass^ CustomTimerClassInput, Variables^ variableReference)
{
customTimerRef = CustomTimerClassInput;
variableRef = gcnew Variables (CustomTimerClassInput);
}
void displayMessage(Object^ sender, TimerEventArgs^ timer)
{
counter ++;
if (counter > 0)
{
variableRef->Flag = true;
Console::WriteLine("Message: an event occured at time stamp: " + timer->EventTime);
}
}
};