체크갯수확인 checkbox

<script type="text/javascript">

<!--

$(function(){

$("input#ss").click(function(){

var ss = $("input:checkbox[name=famIdx[]]:checked").length;    //체크갯수확인

if(ss>2){

alert("경고");

}else{

alert("G"+ss);

}

});

});

//-->

</script>

<form>

<input type="checkbox" name="infro[]" value="1" />1

<input type="checkbox" name="infro[]" value="2" />2

<input type="checkbox" name="infro[]" value="3" />3

<input type='image' id="ss" src='2' title='2'/>

</form>

도움