jquery button submit

====================================

  $('#btn_search').click(function(){

if(!$("#s_k").val()){

                      alert('검색어를 입력해 주십시오.');

  $("#s_k").focus();

      return false;

   }

$('#search_f').submit();

   });

=================================

<div class='search_box search_box_po1'>

<form method=get action="<?=$PHP_SELF?>" id=search_f >

<input type=hidden name=s_type value=t <?=$s_type1?> />

<ul>

<li><label for="s_k" class="hidden">기사검색</label><input type='text' name='s_k' id="s_k" value="<?=$s_k?>" placeholder="기사검색" /></li>

<li><label for="btn_search" class="hidden">검색</label><input type='button' id="btn_search" value='검색' class="btn_normal3 input_btn" /></li>

</ul>

</form>

</div>