将短代码中的项目转换为数组，并返回列表：

add_shortcode( \'features_list\', \'shortcode_features_list\' );

function shortcode_features_list( $atts = array(), $content = \'\' )
{
    $content = trim( $content );

    if ( \'\' === $content )
        return;

    $items = explode( "\\n", $content );

    $items = array_map( \'trim\', $items );

    return \'<ul class="features"><li>\' . join( \'</li><li>\', $items ) . \'</li></ul>\';
}