PHP删除重复的XML提要条目

Hi i'm parsing an XML file using PHP to create another XML file in a nicer format which I am eventually going to use to populate an unordered HTML list.

But the XML feed has duplicate entries, and thus my formatted output also has duplicate entries. How can i loop through the feed and remove the duplicates somehow? Using PHP if possible. I'm a bit of a newbie and am not sure what to do with this one.

Here is a typical output (my formatted XML with duplicates):

    <films>
    <film>
    <filmtitle>Death Race 2</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=377029</filmlink>
    </film>

    <film>
    <filmtitle>Death Race 2</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=377029</filmlink>
    </film>

    <film>
    <filmtitle>Shattered Glass</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=UKIC48</filmlink
    </film>

    <film>
    <filmtitle>Shattered Glass</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=UKIC48</filmlink>
    </film>

    <film>
    <filmtitle>The Brothers Bloom</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=380196</filmlink>
    </film>

    <film>
    <filmtitle>The Brothers Bloom</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=380196</filmlink>
    </film>

...and so on...

Any help would be great. Thanks.

UPDATE:

I have defined an array before looping through the feed like this:

$filmList = array();

When looping throughout the list I have added entries using:

array_push($filmsForList, array("filmTitle" => $title, "pictureLink" => $pictureLink);

where $filmTitle and $filmLink are the values from the parsed XML. How would I remove duplicates from that? Or stop them entering in the first place?

Thanks...

Just put those pairs in an array, use title as key, link as value. You would simply override duplicates when inserting into the array.

See this question for a discussion about Java hashmaps and PHP arrays.

Edit:

Something like this:

$a = array("one" => "one_link", "two" => "two_link", "one" => "one_link");

$target = array();

foreach ($a as $key => $value)
   $target[$key] = $value;

This will get you:

array("one" => "one_link", "two" => "two_link")

With this setup, there is no need to check if the key already exists.

Try this:

<?php
$str=<<<'EOT'
    <films>
    <film>
    <filmtitle>Death Race 2</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=377029</filmlink>
    </film>

    <film>
    <filmtitle>Death Race 2</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=377029</filmlink>
    </film>

    <film>
    <filmtitle>Shattered Glass</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=UKIC48</filmlink>
    </film>

    <film>
    <filmtitle>Shattered Glass</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=UKIC48</filmlink>
    </film>

    <film>
    <filmtitle>The Brothers Bloom</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=380196</filmlink>
    </film>

    <film>
    <filmtitle>The Brothers Bloom</filmtitle>
    <filmlink>http://www.picturebox.tv/watchnow?id=380196</filmlink>
    </film>
    </films>
EOT;

$xml=simplexml_load_string($str);

$seen=array();

$len=$xml->film->count();
for($i=0;$i<$len;$i++){
    $key=(string) $xml->film[$i]->filmlink;
    if (isset($seen[$key])) {
        unset($xml->film[$i]);
        $len--;
        $i--;
    }else{
        $seen[$key]=1;
    }
}

echo $xml->asXML();

?>

this clears duplicates by filmlink