<script language=javascript>
function selectall() //全选
{
var arrobj = document.all;
for(var i = 0; i < arrobj.length;i++)
{
if(typeof arrobj[i].type != undefined && arrobj[i].type=='checkbox') arrobj[i].checked =true;
}
}
function unselectall() //全不选
{
var arrobj = document.all;
for(var i = 0; i < arrobj.length;i++)
{
if(typeof arrobj[i].type != undefined && arrobj[i].type=='checkbox') arrobj[i].checked =false;
}
}
</script>