runform.pas

用delphi实现的PL/0的编译器

unit RunForm;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls;

type
  TfrmRun = class(TForm)
    mView: TMemo;
    procedure mViewKeyPress(Sender: TObject; var Key: Char);
  private
    { Private declarations }
  public
    { Public declarations }
    rVal:string;
    rKey:Char;
    readed:boolean;    
    function WantVal:integer;
  end;

var
  frmRun: TfrmRun;

implementation

{$R *.DFM}

function TfrmRun.WantVal:integer;
begin
 WantVal:=StrToInt(rVal);
 rVal:='';
end;

procedure TfrmRun.mViewKeyPress(Sender: TObject; var Key: Char);
begin
 if (Key=#13) and (frmRun.tag=1) then Close;
 if not(Key in ['0'..'9']+[#13,#8]) then
  begin
   Key:=#0;
   exit;
  end;
 if (Key=#13) and (rVal='') then
  begin
   Key:=#0;
   exit;
  end;
 if (Key=#8) and (length(rVal)=0) then
  begin
   Key:=#0;
   exit;
  end;
 if (Key=#13) and (frmRun.readed=false) and (rVal<>'') then frmRun.readed:=true;
 if (not frmRun.readed) and (Key<>#13) then
  begin
   if Key=#8 then
    begin
     if length(rVal)>0 then delete(rVal,length(rVal),1);
    end
   else rVal:=rVal+Key;
  end;
end;

end.