Show first n paragraphs - WordPress

gistfile1.php

<?php

// FILTER POST CONTENT - SHOWS FIRST N PARAGRAPHS

function filter_content_n_paragraphs( $content ) {
  $stopat = 2; // how many paragraphs you want to display (n)
	$paragraphno = $stopat - 1; // computers start at 0

	// conditions to meet for filtering content
	if( !is_user_logged_in() ) {
		$paras = explode( '</p>', $content );
		// check whether article is at least n paragraphs long
		if( count( $paras ) > $paragraphno ) {
			$i = 0;
			// show paragraph while less than our paragraph no
			while( $i <= $paragraphno ) {
				echo $paras[$i];
				$i++;
			}
		}
		// how the user can see all the content
		return gravity_form(2, false, true, false);
	} else {
		return $content;
	}
}

add_filter( 'the_content', 'filter_content_n_paragraphs' );