WPquestions.com #2394 rev1

gistfile1.php

<?php
/**** ADD FB IMAGES***/

//Adding the Open Graph in the Language Attributes
function add_opengraph_doctype( $output ) {
	return $output . ' xmlns:og="http://opengraphprotocol.org/schema/" xmlns:fb="http://www.facebook.com/2008/fbml"';
}
add_filter('language_attributes', 'add_opengraph_doctype');

//Lets add Open Graph Meta Info
function insert_fb_in_head() {
	global $post;
	if ( !is_singular()) //if it is not a post or a page
		return;

        echo '<meta property="fb:admins" content="685991022"/>';
        echo '<meta property="og:title" content="' . get_the_title() . '"/>';
        echo '<meta property="og:type" content="article"/>';
        echo '<meta property="og:url" content="' . get_permalink() . '"/>';
        echo '<meta property="og:site_name" content="DDGDaily.com"/>';
	echo '<meta property="og:image" content="' . catch_that_image(false) . '"/>';
	echo "\n";
}

add_action( 'wp_head', 'insert_fb_in_head', 5 );

//grab first image url from post content
// base function from http://www.wprecipes.com/how-to-get-the-first-image-from-the-post-and-display-it
function catch_that_image($inLoop = true) {
	global $post, $posts;
	$first_img = '';
	if ($inLoop) {
		ob_start();
		ob_end_clean();
	}
	$output = preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches);
	$first_img = $matches[1][0];

	if(empty($first_img)){ //Defines a default image
		$first_img = home_url("/wp-content/uploads/newavatar.png");
	}
	return $first_img;
}
?>