递归下降语法分析器dlg.cpp

编译原理的词法分析,做递归下降分析的

// 递归下降语法分析器Dlg.cpp : implementation file
//

#include "stdafx.h"
#include "递归下降语法分析器.h"
#include "递归下降语法分析器Dlg.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()

/////////////////////////////////////////////////////////////////////////////
// CMyDlg dialog

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

void CMyDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CMyDlg)
	DDX_Text(pDX, IDC_CODE, m_code);
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CMyDlg, CDialog)
	//{{AFX_MSG_MAP(CMyDlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_ANALYSE, OnAnalyse)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMyDlg message handlers

BOOL CMyDlg::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
	SetDlgItemText(IDC_WENFA,
		"E->TE'\r\n\r\nE'->+TE'|$\r\n\r\nT->FT'\r\n\r\nT'->*FT'\r\n\r\nF->(E)|i");
	SetDlgItemText(IDC_ANSWER,"请输入待分析语句。");

	return TRUE;  // return TRUE  unless you set the focus to a control
}

void CMyDlg::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 CMyDlg::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 CMyDlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

void CMyDlg::OnAnalyse() 
{
	// TODO: Add your control notification handler code here
	UpdateData(true);
	int i = 0;
	s.empty();
	s.push('#');
	s.push('E');
	m_code += '#';
	strAnswer = "";
	if(G_E_Te(i))
	{
		strAnswer = "符合此文法！！";
	}
	MessageBox(strAnswer);
	SetDlgItemText(IDC_ANSWER,strAnswer);
}

bool CMyDlg::BeginAnalyse(int &i)
{
	bool flag = false;
	char temp = s.top();
	switch(temp)
	{
	case 'E':
		flag = G_E_Te(i);
		break;
	case 'e':
		flag = G_e_Te_$(i);
		break;
	case 'T':
		flag = G_T_Ft(i);
		break;
	case 't':
		flag = G_t_Ft_$(i);
		break;
	case 'F':
		flag = G_F_E_i(i);
		break;
	case '#':
		flag = G_t_Ft_$(i);
		break;
	case ')':
		flag = G_E_Te(i);
	}
	return flag;
}
/////////////////////////////////////////////////////////
bool  CMyDlg::G_E_Te(int &i)
{
	char temp = s.top();
	bool flag = false;
	if(temp == m_code[i])
	{
		i++;
		s.pop();
		return BeginAnalyse(i);
	}
	temp = s.top();
	if(m_code[i] == 'i' || m_code[i] == '(')
	{
		s.pop();
		s.push('e');
		s.push('T');
		flag = G_T_Ft(i);
	}
	else
	{
		strAnswer += "E->TE'处出错！\r\n";
	}
	return flag;
}
////////////////////////////////////////////////////////////////
bool  CMyDlg::G_e_Te_$(int &i)
{
	char temp = s.top();
	bool flag = false;
	if(temp == m_code[i])
	{
		i++;
		s.pop();
		if(temp == '#')
			return true;
		return BeginAnalyse(i);
	}
	temp = s.top();
	if(m_code[i] == '+')
	{
		s.pop();
		s.push('e');
		s.push('T');
		s.push('+');
		flag = G_e_Te_$(i);
	}
	else if(m_code[i] == ')' || m_code[i] == '#')
	{
		s.pop();
		flag = BeginAnalyse(i);
	}
	else
	{
		strAnswer += "E'->+TE'|$处出错！\r\n";
	}
	return flag;
}
//////////////////////////////////////////////////////////////////////////////
bool  CMyDlg::G_T_Ft(int &i)
{
	char temp = s.top();
	bool flag = false;
	if(temp == m_code[i])
	{
		i++;
		s.pop();
		return BeginAnalyse(i);
	}
	temp = s.top();
	if(m_code[i] == 'i' || m_code[i] == '(')
	{
		s.pop();
		s.push('t');
		s.push('F');
		flag = G_F_E_i(i);
	}
	else
	{
		strAnswer += "T->FT''处出错！\r\n";
	}
	return flag;
}
/////////////////////////////////////////////////////////////////////////////////
bool  CMyDlg::G_t_Ft_$(int &i)
{
	char temp = s.top();
	bool flag = false;
	if(temp == m_code[i])
	{
		i++;
		s.pop();
		if(temp == '#')
			return true;
		return BeginAnalyse(i);
	}
	temp = s.top();
	if(m_code[i] == '*')
	{
		s.pop();
		s.push('t');
		s.push('F');
		s.push('*');
		flag = G_t_Ft_$(i);
	}
	else if(m_code[i] == '+' || m_code[i] == ')' || m_code[i] == '#')
	{
		s.pop();
		flag = BeginAnalyse(i);
	}
	else
	{
		strAnswer += "T'->*FT'|$处出错！\r\n";
	}
	return flag;
}
/////////////////////////////////////////////////////////////////////////////////
bool  CMyDlg::G_F_E_i(int &i)
{
	char temp = s.top();
	bool flag = false;
	if(temp == m_code[i])
	{
		i++;
		s.pop();
		return BeginAnalyse(i);
	}
	temp = s.top();
	if(m_code[i] == '(')
	{
		s.pop();
		s.push(')');
		s.push('E');
		s.push('(');
		flag = G_F_E_i(i);
	}
	else if(m_code[i] == 'i')
	{
		s.pop();
		s.push('i');
		flag = G_F_E_i(i);
	}
	else
	{
		strAnswer += "F->(E)|i处出错！\r\n";
	}
	return flag;
}
///////////////////////////////////////////////////////////////////////////////////