bysy2dlg.cpp

编译算法中有关语法分析的源代码

// bysy2Dlg.cpp : implementation file
//

#include "stdafx.h"
#include "bysy2.h"
#include "bysy2Dlg.h"
#include "fstream.h"
#include "iostream.h"
#include "string.h"


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

/////////////////////////////////////////////////////////////////////////////
// CAboutDlg dialog used for App About

class CAboutDlg : public CDialog
{
public:
	CAboutDlg();

// Dialog Data
	//{{AFX_DATA(CAboutDlg)
	enum { IDD = IDD_ABOUTBOX };
	//}}AFX_DATA

	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CAboutDlg)
	protected:
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
	//}}AFX_VIRTUAL

// Implementation
protected:
	//{{AFX_MSG(CAboutDlg)
	//}}AFX_MSG
	DECLARE_MESSAGE_MAP()
};

CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
	//{{AFX_DATA_INIT(CAboutDlg)
	//}}AFX_DATA_INIT
}

void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CAboutDlg)
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
	//{{AFX_MSG_MAP(CAboutDlg)
		// No message handlers
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CBysy2Dlg dialog

CBysy2Dlg::CBysy2Dlg(CWnd* pParent /*=NULL*/)
	: CDialog(CBysy2Dlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CBysy2Dlg)
	m_grammar = _T("");
	m_result = _T("");
	m_string = _T("");
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void CBysy2Dlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CBysy2Dlg)
	DDX_Text(pDX, IDC_EDIT_GRAMMAR, m_grammar);
	DDX_Text(pDX, IDC_EDIT_RESULT, m_result);
	DDX_Text(pDX, IDC_EDIT_STRING, m_string);
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CBysy2Dlg, CDialog)
	//{{AFX_MSG_MAP(CBysy2Dlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_BUTTON_ANALYSE, OnButtonAnalyse)
	ON_BN_CLICKED(IDC_BUTTON_CLEAN, OnButtonClean)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CBysy2Dlg message handlers

BOOL CBysy2Dlg::OnInitDialog()
{
	CDialog::OnInitDialog();

	// Add "About..." menu item to system menu.

	// IDM_ABOUTBOX must be in the system command range.
	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
	ASSERT(IDM_ABOUTBOX < 0xF000);

	CMenu* pSysMenu = GetSystemMenu(FALSE);
	if (pSysMenu != NULL)
	{
		CString strAboutMenu;
		strAboutMenu.LoadString(IDS_ABOUTBOX);
		if (!strAboutMenu.IsEmpty())
		{
			pSysMenu->AppendMenu(MF_SEPARATOR);
			pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
		}
	}

	// 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
	

/////////////////////////////////////////////
	m_grammar="E->eBaA"+(CString)13+(CString)10+"A->a|bAcB"+(CString)13+(CString)10+"B->dEd|aC"+(CString)13+(CString)10+"C->e|dc";
	UpdateData(FALSE);
/////////////////////////////////////////////
	return TRUE;  // return TRUE  unless you set the focus to a control
}

void CBysy2Dlg::OnSysCommand(UINT nID, LPARAM lParam)
{
	if ((nID & 0xFFF0) == IDM_ABOUTBOX)
	{
		CAboutDlg dlgAbout;
		dlgAbout.DoModal();
	}
	else
	{
		CDialog::OnSysCommand(nID, lParam);
	}
}

// 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 CBysy2Dlg::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 CBysy2Dlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

char ch[100];
int nchar;
int i;
int process[100],proj;

int E()
{
    int A();
	int B();
	process[proj++]=1;
	if(ch[i]!='e')
		return 0;
	else
	{
		i++;
		if(B()==0)
			return 0;
		else
		{
			if(ch[i]!='a')
				return 0;
			else
			{
				i++;
				if(A()==0)
					return 0;
			}
		}
	}
	return 1;
}

int A()
{
	int B();
	if(ch[i]=='a')
	{
		process[proj++]=2;
		i++;
		return 1;
	}
	else
	{
		process[proj++]=3;
		if(ch[i]!='b')
			return 0;
		else
		{
			i++;
			if(A()==0)
				return 0;
			else
			{
				if(ch[i]!='c')
					return 0;
				else
				{
					i++;
					if(B()==0)
						return 0;
				}
			}
		}
	}
	return 1;
}

int B()
{
	int C();
	if(ch[i]=='d')
	{
		process[proj++]=4;
		i++;
		if(E()==0)
			return 0;
		else
		{
			if(ch[i]!='d')
				return 0;
			else
			{
				i++;
				return 1;
			}
		}
	}
	else
	{
		process[proj++]=5;
		if(ch[i]!='a')
			return 0;
		else
		{
			i++;
			if(C()==0)
				return 0;
		}
	}
	return 1;
}

int C()
{
	if(ch[i]=='e')
	{
		process[proj++]=6;
		i++;
		return 1;
	}
	else
	{
		process[proj++]=7;
		if(ch[i]!='d')
			return 0;
		else
		{
			i++;
			if(C()==0)
				return 0;
			else 
				return 1;
		}
	}
}
void CBysy2Dlg::OnButtonAnalyse() 
{
	UpdateData(TRUE);
	strcpy(ch,m_string);/*把CString类型的字符串转化成了字符数组*/
	i=0;
	proj=0;
	CString procc="";
	int flag=E();
	for(int j=0;j<proj;j++)
	{
		if(process[j]==1)
			procc=procc+"E->eBaA"+(CString)13+(CString)10;
		else if(process[j]==2)
			procc=procc+"A->a"+(CString)13+(CString)10;
		else if(process[j]==3)
			procc=procc+"A->bAcB"+(CString)13+(CString)10;		
	    else if(process[j]==4)
			procc=procc+"B->dEd"+(CString)13+(CString)10;
		else if(process[j]==5)
			procc=procc+"B->aC"+(CString)13+(CString)10;
		else if(process[j]==6)
			procc=procc+"C->e"+(CString)13+(CString)10;
		else
			procc=procc+"C->dC"+(CString)13+(CString)10;
	}
	if(flag)
		m_result=m_string+"为合法符号串"+(CString)13+(CString)10+"推导过程："+(CString)13+(CString)10+procc;
	else
		m_result=m_string+"为非法符号串"+(CString)13+(CString)10+"推导过程："+(CString)13+(CString)10+procc+"无法继续推导下去";
    UpdateData(FALSE);

}

void CBysy2Dlg::OnButtonClean() 
{
	m_string="";
	m_result="";
	UpdateData(FALSE);
}