main.pas

~~~ ~~在编译原理实验中,用Delphi实现词法分析的实现

unit MAIN;

interface

uses Windows, SysUtils, Classes, Graphics, Forms, Controls, Menus,
  StdCtrls, Dialogs, Buttons, Messages, ExtCtrls, ComCtrls, StdActns,
  ActnList, ToolWin, ImgList;

type
  TMainForm = class(TForm)
    MainMenu1: TMainMenu;
    File1: TMenuItem;
    FileNewItem: TMenuItem;
    FileOpenItem: TMenuItem;
    FileCloseItem: TMenuItem;
    Window1: TMenuItem;
    Help1: TMenuItem;
    N1: TMenuItem;
    FileExitItem: TMenuItem;
    HelpAboutItem: TMenuItem;
    OpenDialog: TOpenDialog;
    FileSaveItem: TMenuItem;
    FileSaveAsItem: TMenuItem;
    Edit1: TMenuItem;
    CutItem: TMenuItem;
    CopyItem: TMenuItem;
    PasteItem: TMenuItem;
    StatusBar: TStatusBar;
    ActionList1: TActionList;
    EditCut1: TEditCut;
    EditCopy1: TEditCopy;
    EditPaste1: TEditPaste;
    FileNew1: TAction;
    FileSave1: TAction;
    FileExit1: TAction;
    FileOpen1: TAction;
    FileSaveAs1: TAction;
    WindowCascade1: TWindowCascade;
    WindowTileHorizontal1: TWindowTileHorizontal;
    WindowArrangeAll1: TWindowArrange;
    WindowMinimizeAll1: TWindowMinimizeAll;
    HelpAbout1: TAction;
    FileClose1: TWindowClose;
    WindowTileVertical1: TWindowTileVertical;
    ToolBar2: TToolBar;
    ToolButton1: TToolButton;
    ToolButton2: TToolButton;
    ToolButton3: TToolButton;
    ToolButton4: TToolButton;
    ToolButton5: TToolButton;
    ToolButton6: TToolButton;
    ToolButton9: TToolButton;
    ToolButton7: TToolButton;
    ToolButton8: TToolButton;
    ToolButton10: TToolButton;
    ToolButton11: TToolButton;
    ImageList1: TImageList;
    Splitter1: TSplitter;
    Panel1: TPanel;
    Panel2: TPanel;
    Splitter2: TSplitter;
    Panel3: TPanel;
    Splitter3: TSplitter;
    Memo1: TMemo;
    N2: TMenuItem;
    N3: TMenuItem;
    N4: TMenuItem;
    N5: TMenuItem;
    N6: TMenuItem;
    N7: TMenuItem;
    N8: TMenuItem;
    Memo2: TMemo;
    Memo3: TMemo;
    Memo4: TMemo;
    procedure FileNew1Execute(Sender: TObject);
    procedure FileOpen1Execute(Sender: TObject);
    procedure HelpAbout1Execute(Sender: TObject);
    procedure FileExit1Execute(Sender: TObject);
    procedure N8Click(Sender: TObject);
    procedure N3Click(Sender: TObject);
  private
    { Private declarations }
    procedure CreateMDIChild(const Name: string);
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation

{$R *.dfm}

uses CHILDWIN, about;

procedure TMainForm.CreateMDIChild(const Name: string);
var
  Child: TMDIChild;
begin
  { create a new MDI child window }
  Child := TMDIChild.Create(Application);
  Child.Caption := Name;
  if FileExists(Name) then Child.Memo1.Lines.LoadFromFile(Name);
end;

procedure TMainForm.FileNew1Execute(Sender: TObject);
begin
  CreateMDIChild('NONAME' + IntToStr(MDIChildCount + 1));
end;

procedure TMainForm.FileOpen1Execute(Sender: TObject);
begin
  if OpenDialog.Execute then
  begin
    memo3.Clear;
    memo4.Clear;
    memo2.lines.loadfromfile(openDialog.FileName);
  end
end;

procedure TMainForm.HelpAbout1Execute(Sender: TObject);
begin
  AboutBox.ShowModal;
end;

procedure TMainForm.FileExit1Execute(Sender: TObject);
begin
  Close;
end;
{
procedure judge(Sender: TObject)
var
  i,flag:integer;
  
begin
  flag:=0;
  if (fs[1]>'A')and(fs[1]<'z') then
  begin
      for i:=0 to 24 do
      begin
          if fs=memo1.Lines[i] then
          begin
            flag:=1;
            memo3.Lines.Add(fs+'i+1');
            break;
          end;
      end;
  end;
end;
 }

  //识别单词
procedure ready(t:string;l:integer);
var
  i:integer;
  fs:string;
begin
  fs:='';
  for i:=1 to l do
  begin
    if (t[i]>='A')and(t[i]<='z') then         //字母识别
    begin
        if fs='' then
           fs:=fs+t[i]
        else
        begin
           if ((fs[1]>='z')or(fs[1]<='A'))and((fs[1]>='9')or(fs[1]<='0')) then
           begin
                MainForm.Memo3.Lines.Add(fs);        //输出运算符
                fs:='';
                fs:=fs+t[i];
           end
           else fs:=fs+t[i];
        end;
    end

    else if (t[i]>='0')and(t[i]<='9') then        //数字识别
     begin
        if fs='' then
        begin
           fs:=fs+t[i];
        end
        else
        begin
          if ((fs[1]>='A')and(fs[1]<='z'))or((fs[1]>='0')and(fs[1]<='9')) then
              fs:=fs+t[i]
          else
          begin
              MainForm.Memo3.Lines.Add(fs);
              fs:='';
              fs:=fs+t[i];
          end;
        end;
    end

    else              //特殊符号识别
    begin
        if fs<>'' then
        begin
          if ((fs[1]>='A')and(fs[1]<='z'))or((fs[1]>='0')and(fs[1]<='9')) then
          begin
              MainForm.Memo3.Lines.Add(fs);
              fs:='';
              fs:=fs+t[i];
          end
          else
          begin
              if t[i]='=' then
              begin
                 if (fs[1]='<')or(fs[1]='>')or(fs[1]=':') then
                 begin
                    fs:=fs+t[i];
                    MainForm.Memo3.Lines.Add(fs);
                    fs:='';
                 end;
              end;
          end;
        end
        else fs:=fs+t[i];
    end;
  end;
  if fs<>'' then
  begin
    MainForm.memo3.Lines.Add(fs);
    fs:='';
  end;
  //MainForm.Memo3.Lines.SaveToFile('f:\token.txt');
end;

procedure TMainForm.N8Click(Sender: TObject);
var
  t,temp:string;
  i,j:integer;
  len,len1:integer;
begin
    //初始化
    temp:='';  t:='';
    len:=0;

    //查找出一字符串
    for i:=0 to memo2.Lines.Count-1 do
    begin
        len:=length(memo2.Lines[i]);     //计算一行字符串的长度
        temp:=memo2.Lines[i];            //保存该行字符串

        for j:=1 to len do              //将字符串中的单词 数字或表达式识别出来
        begin
            if (temp[j]=' ') then
            begin
               if t<>'' then
               begin
                  len1:=length(t);        //识别出来的字符串长度
                  ready(t,len1);          //处理识别出来的字符串
                  t:='';
               end;
            end
            else t:=t+temp[j];

        end;

        if t<>'' then        //遇到换行的处理
        begin
              len1:=length(t);
              ready(t,len1);
              t:='';
        end;

        temp:='';
    end;

end;

procedure TMainForm.N3Click(Sender: TObject);
var
 i:integer;
begin
  memo4.Lines.Add('%%%%%%   开始语法分析 %%%%%% ');
for i:=0 to memo3.Lines.Count-1 do
 begin
  if memo3.Lines[0]<>'program'  then
   begin
   memo4.Lines.Add('ERROR!!!首字符串为program!!语法分析结束!!');
   break;
   end
   else
memo4.Lines.Add(memo3.Lines[i]);
end;
end;

end.