Convert html table to aray.php

<?php 
//============ ============  ============  ============ 
// Convert html table to aray
// 
// @auth: ViHoangSon
// @since: 20160704092752
// 
// Using:
// $contents = "<table><tr><td>Row 1 Column 1</td><td>Row 1 Column 2</td></tr><tr><td>Row 2 Column 1</td><td>Row 2 Column 2</td></tr></table>";
// $array = ConvertHelper::getdata($contents);
//============ ============  ============  ============ 
class ConvertHelper{
	static function getdata($contents)
	{
		$DOM = new DOMDocument;
		$DOM->loadHTML($contents);
		$items = $DOM->getElementsByTagName('tr');
		$return = array();
		foreach ($items as $node) {
			$return[] = self::tdrows($node->childNodes);
		}
		return $return;
	}

	static function tdrows($elements)
	{
		$str = array();
		foreach ($elements as $element) {
			$str[] = $element->nodeValue;
		}

		return $str;
	}
}
 ?>

Hello, i got an issue,

the TD are not in the array