下面的例子简单的演示了DOM对XML的操作,详细解释请看代码中的注释
复制代码 代码如下:
/************************************************
** use XML in PHP5
** reference site:
** http://cn.php.net/manual/zh/ref.dom.php
** the follow codes need PHP5 support
*************************************************/
//首先要创建一个DOMDocument对象
$dom = new DomDocument();
//然后载入XML文件
$dom -> load("test.xml");
//输出XML文件
//header("Content-type: text/xml;charset=gb2312");
//echo $dom -> saveXML();
//保存XML文件,返回值为int(文件大小,以字节为单位)
//$dom -> save("newfile.xml");
echo "
取得所有的title元素:
";
$titles = $dom -> getElementsByTagName("title");
foreach ($titles as $node){
echo $node -> textContent . "
";
//这样也可以
//echo $node->firstChild->data . "
";
}
/*
echo "
从根结点遍历所有结点:
";
foreach ($dom->documentElement->childNodes as $items) {
//如果节点是一个元素(nodeType == 1)并且名字是item就继续循环
if ($items->nodeType == 1 && $items->nodeName == "item") {
foreach ($items->childNodes as $titles) {
//如果节点是一个元素,并且名字是title就打印它.
if ($titles->nodeType == 1 && $titles->nodeName == "title") {
print $titles->textContent . "\n";
}
}
}
}
*/
//使用XPath查询数据
echo "
使用XPath查询的title节点结果:
";
$xpath = new domxpath($dom);
$titles = $xpath->query("/rss/channel/item/title");
foreach ($titles as $node){
echo $node->textContent."
";
}
/*
这样和使用getElementsByTagName()方法差不多,但是Xpath要强大的多
深入一点可能是这样:
/rss/channel/item[position() = 1]/title 返回第一个item元素的所有
/rss/channel/item/title[@id = '23'] 返回所有含有id属性并且值为23的title
/rss/channel/&folder&/title 返回所有articles元素下面的title(译者注:&folder&代表目录深度)
*/
//向DOM中写入新数据
$item = $dom->createElement("item");
$title = $dom->createElement("title");
$titleText = $dom->createTextNode("title text");
$title->appendChild($titleText);
$item->appendChild($title);
$dom->documentElement->getElementsByTagName('channel')->item(0)->appendChild($item);
//从DOM中删除节点
//$dom->documentElement->RemoveChild($dom->documentElement->getElementsByTagName("channel")->item(0));
//或者使用xpath查询出节点再删除
//$dom->documentElement->RemoveChild($xpath->query("/rss/channel")->item(0));
//$dom->save("newfile.xml");
//从DOM中修改节点数据
//修改第一个title的文件
//这个地方比较笨,新创建一个节点,然后替换旧的节点。如果哪位朋友有其他好的方法请一定要告诉我
$firstTitle = $xpath->query("/rss/channel/item/title")->item(0);
$newTitle = $dom->createElement("title");
$newTitle->appendChild(new DOMText("This's the new title text!!!"));
$firstTitle->parentNode->replaceChild($newTitle, $firstTitle);
//修改属性
//$firstTitle = $xpath->query("/rss/channel/item/title")->item(0);
//$firstTitle->setAttribute("orderby", "4");
$dom->save("newfile.xml");
echo "
查看newfile.xml";
//下面的代码获得并解析php.net的首页,将返第一个title元素的内容。
/*
$dom->loadHTMLFile("http://www.php.net/");
$title = $dom->getElementsByTagName("title");
print $title->item(0)->textContent;
*/
?>
下面是test.xml文件代码:
复制代码 代码如下:
http://blog.csdn.net/zhongmao/category/29515.aspx
http://blog.csdn.net/zhongmao/archive/2004/09/15/105385.aspx
http://blog.csdn.net/zhongmao/archive/2004/08/06/67161.aspx
http://blog.csdn.net/zhongmao/archive/2004/08/02/58417.aspx

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