reportclass.cpp

华东理工大学李英所著《Visual C++编程与项目开发》的源代码。 本书简明扼要

// ReportClass.cpp : implementation file
//

#include "stdafx.h"
#include "ExMIS.h"
#include "ReportClass.h"

//数学计算类
#include "Math.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CReportClass dialog


CReportClass::CReportClass(CWnd* pParent /*=NULL*/)
	: CDialog(CReportClass::IDD, pParent)
{
	//{{AFX_DATA_INIT(CReportClass)
	m_n100 = 0;
	m_n50 = 0;
	m_n60 = 0;
	m_n70 = 0;
	m_n80 = 0;
	m_n90 = 0;
	m_fAvg = 0.0f;
	m_nCount = 0;
	m_fDelta = 0.0f;
	m_fHigh = 0.0f;
	m_fLow = 0.0f;
	//}}AFX_DATA_INIT
}


void CReportClass::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CReportClass)
	DDX_Text(pDX, IDC_EDIT_100, m_n100);
	DDX_Text(pDX, IDC_EDIT_50, m_n50);
	DDX_Text(pDX, IDC_EDIT_60, m_n60);
	DDX_Text(pDX, IDC_EDIT_70, m_n70);
	DDX_Text(pDX, IDC_EDIT_80, m_n80);
	DDX_Text(pDX, IDC_EDIT_90, m_n90);
	DDX_Text(pDX, IDC_EDIT_AVG, m_fAvg);
	DDX_Text(pDX, IDC_EDIT_COUNT, m_nCount);
	DDX_Text(pDX, IDC_EDIT_DELTA, m_fDelta);
	DDX_Text(pDX, IDC_EDIT_HIGH, m_fHigh);
	DDX_Text(pDX, IDC_EDIT_LOW, m_fLow);
	//}}AFX_DATA_MAP
}


BEGIN_MESSAGE_MAP(CReportClass, CDialog)
	//{{AFX_MSG_MAP(CReportClass)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CReportClass message handlers

BOOL CReportClass::OnInitDialog() 
{
	CDialog::OnInitDialog();
	

	//打开数据集
	m_pRS.ADOOpen();
	//计算
	Calculate(m_strClassID);
	
	
	return TRUE;  // return TRUE unless you set the focus to a control
	              // EXCEPTION: OCX Property Pages should return FALSE
}

//统计计算
void CReportClass::Calculate(CString classID)
{
	//先打开数据集；
	m_pRS.ADOOpen();

	//清空所有	
	m_fLow = 0.0f;
	m_fHigh = 0.0f;
	m_fDelta = 0.0f;
	m_fAvg = 0.0f;
	m_n90 = 0;
	m_n80 = 0;
	m_n70 = 0;
	m_n60 = 0;
	m_n50 = 0;
	m_n100 = 0;
	m_nCount = 0;
	
	CString sql;
	//先提出某门课程的平均分
	sql.Format("SELECT Avg(Score) FROM ScoreTab WHERE ClassID='%s'",classID);
	m_pRS.ADOExcute(sql);
	//因为ACCESS中提取的平均数是字符类型
	m_fAvg=atof(m_pRS.GetFieldString(0));

	m_fHigh=m_fAvg;
	m_fLow=m_fAvg;

	//再算出标准差
	float sum,score;
	sum=0;
	sql.Format("SELECT score FROM ScoreTab WHERE ClassID='%s'",classID);
	m_pRS.ADOExcute(sql);
	m_nCount=m_pRS.nFieldRows;
	while(!m_pRS.ADOEOF())
	{
		score=m_pRS.GetFieldFloat(0);
		if(score>m_fHigh)	m_fHigh=score;
		if(score<m_fLow)	m_fLow=score;
		sum+=(score-m_fAvg)*(score-m_fAvg);

		if(score<50)
			m_n50++;
		else if(score<60)
			m_n60++;
		else if(score<70)
			m_n70++;
		else if(score<80)
			m_n80++;
		else if(score<90)
			m_n90++;
		else if(score<=100)
			m_n100++;

		m_pRS.MoveNext();
	}	
	if(m_pRS.nFieldRows>1){
		//标准差公式
		m_fDelta=sqrt(sum/(m_pRS.nFieldRows-1));
	}else{
		m_fDelta=0;
	}

	UpdateData(false);
}