calctestdlg.cpp

这源代码是《白领就业指南：visual c++ 6.0 设计师之路》的配套源代码

// CalcTestDlg.cpp : implementation file
//

#include "stdafx.h"
#include "CalcTest.h"
#include "CalcTestDlg.h"

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

/////////////////////////////////////////////////////////////////////////////
// CCalcTestDlg dialog

CCalcTestDlg::CCalcTestDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CCalcTestDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CCalcTestDlg)
	m_exp = _T("");
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void CCalcTestDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CCalcTestDlg)
	DDX_Text(pDX, IDC_EXP, m_exp);
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CCalcTestDlg, CDialog)
	//{{AFX_MSG_MAP(CCalcTestDlg)
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_BUTTON_YINSHI, OnButtonYinshi)
	ON_BN_CLICKED(IDC_BUTTON_XIAN, OnButtonXian)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CCalcTestDlg message handlers

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

	// Set the icon for this dialog.  The framework does this automatically
	//  when the application's main window is not a dialog
	SetIcon(m_hIcon, TRUE);			// Set big icon
	SetIcon(m_hIcon, FALSE);		// Set small icon
	
	// TODO: Add extra initialization here
	
	return TRUE;  // return TRUE  unless you set the focus to a control
}

// If you add a minimize button to your dialog, you will need the code below
//  to draw the icon.  For MFC applications using the document/view model,
//  this is automatically done for you by the framework.

void CCalcTestDlg::OnPaint() 
{
	if (IsIconic())
	{
		CPaintDC dc(this); // device context for painting

		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);

		// Center icon in client rectangle
		int cxIcon = GetSystemMetrics(SM_CXICON);
		int cyIcon = GetSystemMetrics(SM_CYICON);
		CRect rect;
		GetClientRect(&rect);
		int x = (rect.Width() - cxIcon + 1) / 2;
		int y = (rect.Height() - cyIcon + 1) / 2;

		// Draw the icon
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
}

// The system calls this to obtain the cursor to display while the user drags
//  the minimized window.
HCURSOR CCalcTestDlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

void CCalcTestDlg::OnButtonYinshi() 
{
	// TODO: Add your control notification handler code here
	UpdateData(true);
	if(m_exp.IsEmpty())
	{
		AfxMessageBox("请先输入四则运算表达式：");
		return;
	}
	if(!TestExp(m_exp))
	{
		AfxMessageBox("格式错，请输入类似 \n -(-5+3*2)/2+1 \n这样的四则表达式");
		return;
	}
	HMODULE hDll=::LoadLibrary(".\\Calc.dll");//加载链接库 
	if(hDll==NULL){ 
		MessageBox("找不到Calc.dll,加载动态链接库失败","Warning",MB_OK|MB_ICONWARNING); 
		return;} 
	typedef double (*pShow)(const char *); 
	pShow Show=(pShow)::GetProcAddress(hDll,"Calc"); 
	if(Show==NULL)
		MessageBox("函数调用失败","Warning",MB_OK|MB_ICONWARNING); //调用加载动态链接库失败
	else 				
		m_exp.Format("%f",Show(m_exp)); 	

	FreeLibrary(hDll);
	UpdateData(false);
}

void CCalcTestDlg::OnButtonXian() 
{
	// TODO: Add your control notification handler code here
	UpdateData(true);
	if(m_exp.IsEmpty())
	{
		AfxMessageBox("请先输入四则运算表达式：");
		return;
	}
	if(!TestExp(m_exp))
	{
		AfxMessageBox("格式错，请输入类似 \n -(-5+3*2)/2+1 \n这样的四则表达式");
		return;
	}
	CString filter,strPath;
	filter="Dll(*.dll)|*.dll||"; 
	CFileDialog dlg(TRUE,NULL,"Calc.dll",OFN_HIDEREADONLY,filter); 

	if(dlg.DoModal()==IDOK) 
		strPath=dlg.GetPathName(); 

	HMODULE hDll=::LoadLibrary(strPath);//加载链接库 
	if(hDll==NULL){ 
		MessageBox("加载动态链接库失败","Warning",MB_OK|MB_ICONWARNING); 
		return;} 
	typedef double (*pShow)(const char []); 
	pShow Show=(pShow)::GetProcAddress(hDll,"Calc"); 
	if(Show==NULL)
		MessageBox("函数调用失败","Warning",MB_OK|MB_ICONWARNING); //调用加载动态链接库失败
	else 
		m_exp.Format("%f",Show(m_exp)); 

	FreeLibrary(hDll);
	
	UpdateData(FALSE); 
}

bool CCalcTestDlg::TestExp(const char *str)
{
	char ch;
	int len=strlen(str),i=0;	
	while(len)
	{
		ch=*(str+i++);
		if(i==len+1)
				return true;
		if(ch>='0' &&ch<='9' || ch=='+' || ch=='-' || ch=='*' ||ch=='/' ||ch=='(' ||ch==')')
			;
		else
			return false;
	}
	return true;		
}