DEDECMS给list标签加上多字段排序功能

//假如不消默认的sortrank或id排序，利用连系查询（数据量大时很是迟钝）
if(preg_match('/hot|click|lastpost|title/', $orderby))
	       {
	           $query = "SELECT arc.*,tp.typedir,tp.typename,tp.isdefault,tp.defaultname,
	          tp.namerule,tp.namerule2,tp.ispart,tp.moresite,tp.siteurl,tp.sitepath
	          $addField
	          FROM `js_archives` arc
	          LEFT JOIN `js_arctype` tp ON arc.typeid=tp.id
	          $addJoin
	          WHERE {$this->addSql} $ordersql LIMIT $limitstart,$row";
	       }
	       //普通环境先从arctiny表查出ID，然后按ID查询（速度很是快）
	       else
	       {
	           $t1 = ExecTime();
	           $ids = array();
	           $query = "SELECT id FROM `js_arctiny` arc WHERE {$this->addSql} $ordersql LIMIT $limitstart,$row ";
	           $this->dsql->SetQuery($query);
	           $this->dsql->Execute();
	           while($arr=$this->dsql->GetArray())
	           {
	               $ids[] = $arr['id'];
	           }
	           $idstr = join(',',$ids);
	           if($idstr=='')
	           {
	               return '';
	           }
	           else
	           {
	               $query = "SELECT arc.*,tp.typedir,tp.typename,tp.corank,tp.isdefault,tp.defaultname,
	                      tp.namerule,tp.namerule2,tp.ispart,tp.moresite,tp.siteurl,tp.sitepath
	                      $addField
	                      FROM `js_archives` arc LEFT JOIN `js_arctype` tp ON arc.typeid=tp.id
	                      $addJoin
	                      WHERE arc.id in($idstr) $ordersql ";
	           }
	           $t2 = ExecTime();
	           //echo $t2-$t1;
	       }