仔细看看你那两个StringList里面的Strings是否一样。(看你语句应该是Flist和Flist3)
procedure TForm1.Button1Click(Sender: TObject);
s1:=TstringList.Create;
s2:=TstringList.Create ;
for i:=1 to 10 do begin
s1.Append(intTostr(i)+'A');
s2.Append(intTostr(i)+'A');end;
for i:=1 to 10 do
if s2.IndexOf(s1.Strings[I-1])>=0 then
showmessage('Find in '+inttostr(i));
end;end;