找到dede目录下的co_export.php

大概在170行左右

 //获取时间和标题
        $pubdate = $sortrank = time();
        $title = $row->title;
        $litpic = '';
        foreach ($dtp->CTags as $ctag)
        {
            $itemName = $ctag->GetAtt('name');
            if($itemName == 'title' && $usetitle==0)
            {
                $title = trim($ctag->GetInnerText());
                if($title=='')
                {
                    $title = $row->title;
                }
            }
            else if($itemName == 'pubdate')
            {
                $pubdate = trim($ctag->GetInnerText());
                if(preg_match("#[^0-9]#", $pubdate))
                {
                    $pubdate = $sortrank = GetMkTime($pubdate);
                }
               //  else  //将注释部分删掉即可，共4行
               //  {
               //      $pubdate = $sortrank = time();
               //  }
            }
            else if($itemName == 'litpic')
            {
                $litpic = trim($ctag->GetInnerText());
            }
        }