VC中定时器设置

本文简单介绍下VC中定时器设置。

首先，新建对话框应用程序，然后添加几个操作按钮。

定义相关变量

private:
	int m_nValue;

	DWORD m_dwTimeStarted;

	LARGE_INTEGER m_cupHZ;
	LARGE_INTEGER m_StartCount;

源文件

void CTimeCountDlg::OnTimer(UINT nIDEvent)
{
	UpdateData(TRUE);

	switch(nIDEvent)
	{
	case 1:
		{
			m_nValue+=1000;
			m_sValue1.Format("%d",m_nValue);
		}
		break;
	case 2:
		{
			double dbTime = 0;
			dbTime = (::GetTickCount() - m_dwTimeStarted)*1.0;
			m_sValue2.Format("%f",dbTime);
		}
		break;
	case 3:
		{
			double dbTime = 0;
			MSG msg;
			UINT LFactor = 1000;
			while(::GetTickCount() - m_dwTimeStarted < 3*LFactor)
			{
				if (PeekMessage(&msg,0,0,0,PM_REMOVE))
				{
					TranslateMessage(&msg);
					DispatchMessage(&msg);
				}
			}

			dbTime = (::GetTickCount() - m_dwTimeStarted)*1.0;
			m_sValue3.Format("%f",dbTime);
		}
		break;
	case 4:
		{
			UINT LFactor = 1000;
			double dbTimestamp = 0;
			LARGE_INTEGER CurCount;
			QueryPerformanceCounter(&CurCount);
			CurCount.QuadPart = CurCount.QuadPart - m_StartCount.QuadPart;
			dbTimestamp = double(CurCount.QuadPart)*LFactor;
			dbTimestamp = dbTimestamp/double(m_cupHZ.QuadPart);
			m_sValue4.Format("%f",dbTimestamp);
		}
		break;
	default:
		break;
	}

	UpdateData(FALSE);

	CDialog::OnTimer(nIDEvent);
}

void CTimeCountDlg::OnButton1()
{
	m_nValue = 0;
	SetTimer(1,1000,NULL);
	KillTimer(2);
	KillTimer(3);
	KillTimer(4);
}

void CTimeCountDlg::OnButton2()
{
	m_dwTimeStarted = ::GetTickCount();

	SetTimer(2,1000,NULL);
	KillTimer(1);
	KillTimer(3);
	KillTimer(4);
}

void CTimeCountDlg::OnButton3()
{
	m_dwTimeStarted = ::GetTickCount();

	SetTimer(3,1000,NULL);
	KillTimer(1);
	KillTimer(2);
	KillTimer(4);
}

void CTimeCountDlg::OnButton4()
{
	QueryPerformanceFrequency(&m_cupHZ);
	m_StartCount.QuadPart = 0;
	QueryPerformanceCounter(&m_StartCount);

	SetTimer(4,1000,NULL);
	KillTimer(1);
	KillTimer(2);
	KillTimer(3);
}

运行效果

总结：

按钮一：直接使用定时器操作

按钮二：获取操作系统运行时间，然后相减，立即开始

按钮三：获取操作系统运行时间，然后相减，*s内运行或者*s后开始

按钮四：查询定时器计数值

源码下载