从数组中返回若干单元，若数组不存在则返回false

[php]代码库

	/**
	 * Display the table
	 *
	 * @since 3.1.0
	 * @access public
	 */
	function display() {
		extract( $this->_args );

		$this->display_tablenav( 'top' );

?>
<table class="wp-list-table <?php echo implode( ' ', $this->get_table_classes() ); ?>" cellspacing="0">
	<thead>
	<tr>
		<?php $this->print_column_headers(); ?>
	</tr>
	</thead>

	<tfoot>
	<tr>
		<?php $this->print_column_headers( false ); ?>
	</tr>
	</tfoot>

	<tbody id="the-list"<?php if ( $singular ) echo " data-wp-lists='list:$singular'"; ?>>
		<?php $this->display_rows_or_placeholder(); ?>
	</tbody>
</table>
<?php
		$this->display_tablenav( 'bottom' );
	}