How to filter out an iframe from feed

Question

There is some iframe inside post content and I want to get rid of that iframe when the rss feeds are generated. To generate rss feeds, I'm showing full post content.

I started looking at strip_tags() but it does pretty much the opposite: strip everything unless the desired tags.

I'm wondering that maybe there is some hook and some wordpress-y form of solving this issue.

I know I should do something like this:

function rss_noiframe($content) {
    global $post;
    // filter out iframe here
    return $content;
    }

add_filter('the_excerpt_rss', 'rss_noiframe');
add_filter('the_content_feed', 'rss_noiframe');

But I'm lost at this point. Any ideas?

On demand by EAmann, here is some example code that isnt modified at all (it still appears in the feed, in fact):

<iframe src="http://somedomain.net/path/to/frame" frameborder="0" scrolling="no" width="500" height="375"></iframe>

Answer 1

One potential option is to use preg_replace to do a regex match on your content and replace the iframe with empty space.

So this function:

function rss_noiframe($content) {
    $content = preg_replace( '/<iframe(.*)\/iframe>/is', '', $content );

    return $content;
}

add_filter('the_excerpt_rss', 'rss_noiframe');
add_filter('the_content_feed', 'rss_noiframe');

Should automatically convert any instances of <iframe src=...>...</iframe> to a blank.