質問です。MagpieRSSを使っています。
日付順に取得記事をソートしたいのですが、うまくいきません。
アドバイスお願いします。

$rssurl = array ();
$rssurl[] = "http://mainichi.pheedo.jp/f/mainichijp_flash";
$rssurl[] = "http://rss.asahi.com/f/asahi_newsheadlines";

foreach ($rssurl as $pre) {
$url = $pre;
$rss = fetch_rss($url);
$title = $rss->channel['title'];
$title = mb_convert_encoding($title, "shift_jis", "auto");
$url = $rss->channel['link'];
$rss->items = array_slice($rss->items, 0, 1);

foreach ($rss->items as $item ) {
$day = date('n/j',strtotime(substr($item['dc']['date'],0,10)));
$time = date('H:i',strtotime(substr($item['dc']['date'],11,8)));
$date = "$day $time";
$rdf = $item[link];
$article = $item[title];
$article = mb_convert_encoding($article, "shift_jis", "auto");
$linkstr = "$date $rdf $article $url $title<br>\n";
$rssarray["{$date}"] = $linkstr;

krsort($rssarray);
echo "$linkstr";