php XML操作小tip

两个方便的DOMDocument小函数

1. 取唯一节点的值

function getSingleValue($doc,$node){
		return $doc->getElementsByTagName($node)->item(0)->nodeValue;
	}

2. 创建孩子节点

	function createChild($doc,$father,$childname,$value="",$cdata=false){
		$c = $doc->createElement($childname);
		if($value){
			if(!$cdata)
				$text = $doc->createTextNode($value);
			else
				$text = $doc->createCDATASection($value);
			$c->appendChild($text);
		}
		$father->appendChild($c);
		return $c;
	}