stopwatch.h

没有什么可以说的 自己看

// Stopwatch.h: interface for the CStopwatch class.
//
//////////////////////////////////////////////////////////////////////

#if !defined(AFX_STOPWATCH_H__5E9C853C_15D5_42BD_B945_3D5C1A77B481__INCLUDED_)
#define AFX_STOPWATCH_H__5E9C853C_15D5_42BD_B945_3D5C1A77B481__INCLUDED_



#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000

#include "windows.h"

class IStopwatch:public IUnknown
{
public:
	virtual HRESULT _stdcall Start()=0;
	virtual HRESULT _stdcall ElapsedTime(float *Time)=0;
};
		


class CStopwatch : public IStopwatch
{
public:
	CStopwatch();
	virtual ~CStopwatch();

private:
	//	n_mFrequency-->记录时钟频率
	LARGE_INTEGER m_nFrequency;
	
	//	m_nStartTime-->记录开始记时的时间
	LARGE_INTEGER m_nStartTime;

	long m_nReferenceCount;

public:
	HRESULT _stdcall QueryInterface(REFIID riid,void **ppvObject);
	unsigned long _stdcall AddRef();
	unsigned long _stdcall Release();

	//	开始记时，并把开始记时的时间传给m_nStartTime;
	HRESULT _stdcall Start();

	//	将时间差传给Time;
	HRESULT _stdcall ElapsedTime(float *Time);
};
#endif // !defined(AFX_STOPWATCH_H__5E9C853C_15D5_42BD_B945_3D5C1A77B481__INCLUDED_)