procedure TForm1.Button1Click(Sender: TObject);
var
 TstrList:Tstringlist;
 str:string;
begin
 TstrList:=TstringList.Create;
 str:='java';
 TstrList.Add(str);
 TstrList.SaveToFile('c:\jiajia.txt');
 TstrList.Free;end;procedure TForm1.Button2Click(Sender: TObject);
var
 TstrList:Tstringlist;
 sourstr:string;
 descstr:string;
 i:integer;
begin
 try
   sourstr:='java';
   descstr:='delphi';
   TstrList:=Tstringlist.Create;
   TstrList.LoadFromFile('c:\jiajia.txt');
   For i:=0 to TstrList.Count-1 do
    begin
      if TstrList.Strings[i]=sourstr then
         TstrList.Strings[i]:=descstr;
    end;
   TstrList.SaveToFile('c:\jiajia.txt')
 except
   TstrList.Free;
 end;
end;