case of 的使用？

LDWIPMove.EmptyDataSet;
  ADOQuery1.Close;
  ADOQuery1.SQL.Clear;
  ADOQuery1.SQL.Add('SELECT * FROM DBCTicket ');
  ADOQuery1.SQL.Add(' where (BC_Close is null) AND'); 

  case cbb_Prod.ItemIndex of
  0: ADOQuery1.SQL.Add('(BC_po_no LIKE ''HH1%'') AND (BC_Print=''N'') ');
  1: ADOQuery1.SQL.Add('(BC_po_no LIKE ''HH2%'') AND (BC_Print=''N'') ');
  2: ADOQuery1.SQL.Add('(BC_routing_Table = ''HH2_LinkBar'') AND (BC_Print<>''N'')');
  end;


这样写不对吧 CASE OF可以有两个条件吗！应该怎么写啊！！

没看出Case of有什么不对

Switch语句，写法没错

case index of
...
else
...
end;

index是有序数，LZ的写法很正确!