function search()
{
	f = document.forms['sch'];
	if(f.type.value=="" && f.area.value=="" && f.acreage.value=="" && f.added_time.value=="")
	{
		alert("请至少选择一个条件");
		return false;
	}
	window.open("/tenement.php?act=search&intent=lease&type="+f.type.value+"&area="+f.area.value+"&acreage="+f.acreage.value+"&added_time="+f.added_time.value);
}