<form name="f">
<input type="checkbox" name="chkbox[]" id="chkbox" value=1><br>
<input type="checkbox" name="chkbox[]" id="chkbox" value=2><br>
<input type="checkbox" name="chkbox[]" id="chkbox" value=3><br>
<input type="checkbox" name="chkbox[]" id="chkbox" value=4><br>
<input type="checkbox" name="chkbox[]" id="chkbox" value=5><br>
<input type="button" name="but" value="갯수확인" onclick="check_it();">
</form>

<script>
function check_it(){
var from=document.f;
var sum=0;
for (var i=0;i < from.chkbox.length;i++){
if (from.chkbox[i].checked==true){
sum++;
}
}
alert(sum);
}
</script>


폼 전송 받은 페이지에선...

for ($i = 0; $i < $pagesize; $i++) {
if($ac_check[$i]<>''){

$qry_settle="update acount set ac_result='Y',settle_date=$reg_date where ac_no=$ac_check[$i]";
mysql_query($qry_settle) or Error('#43 ');
//ddiass($qry_settle,'qry_settle');
}
}