Read from a file into a multi-selector field in gravity forms

gistfile1.txt

/* http://www.gravityhelp.com/documentation/page/Dynamically_Populating_Drop_Down_Fields
*/
add_filter('gform_pre_render_5', 'populate_posts');
function populate_posts($form){
    
    foreach($form['fields'] as &$field){
        
        if( strpos($field['cssClass'], 'multi-selector') === false) /* original had a check for $field['type'] != 'select' */
            continue;
        
        // you can add additional parameters here to alter the posts that are retreieved
        // more info: http://codex.wordpress.org/Template_Tags/get_posts
        //$posts = get_posts('numberposts=-1&post_status=publish');
        $file = fopen('sites.csv', 'r');
		/*
		while (($line = fgetcsv($file)) !== FALSE) {
		  //$line is an array of the csv elements
		  print_r($line);
		}
		*/
		$line = fgetcsv($file);
		fclose($file);
		$posts=$line;
        
        // update 'Select a Post' to whatever you'd like the instructive option to be
        $choices = array(array('text' => 'Select a Site', 'value' => ' '));
        
        foreach($posts as $post){
           // $choices[] = array('text' => $post->post_title, 'value' => $post->post_title);
           $choices[] = array('text' => $post, 'value'=>$post);
        }
        
        $field['choices'] = $choices;
        
    }
    
    return $form;
}