Thanks krishna
i am using below code
function catch_that_image() {
global $post, $posts;
$first_img = '';
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)) {
$first_img = "https://localhost/goodfood/wp-content/themes/twentyeleven/images/images.jpg";
}
return $first_img;
}
<?php if ( post_password_required() ) : ?>
<?php the_content( __( 'Continue reading <span class="meta-nav">→</span>', 'twentyeleven' ) ); ?>
<?php else : ?>
<?php if ( get_the_post_thumbnail($post_id) != '' ) {
echo '<a href="'; the_permalink(); echo '" class="thumbnail-wrapper">';
the_post_thumbnail();
echo '</a>';
} else {
echo '<a href="'; the_permalink(); echo '" class="thumbnail-wrapper">';
echo '<img src="';
echo catch_that_image();
echo '" alt="" />';
echo '</a>';
}?>