php修改xml节点的值
今天刚刚实现的功能，找了很多资料，本来想用xpath，但是由于对xpath不甚了解。绕了个大圈后还是决定用DOMDocument来做。
在此做一个标记，以后找资料的时候也不用太辛苦。
先从数据库读取数据，然后写一个xml文件。xml文件格式如下。
mainchart.xml
<?xml version="1.0" encoding="utf-8"?>
<records>
<record>
<pono>5008171</pono>
<status>3</status>
<opentime>2010.06.13 14:19</opentime>
<closetime>2010.06.16 14:19</closetime>
<potype>balance</potype>
<variety/>
<margin/>
<openprice/>
<closeprice/>
<zhisun/>
<zhiying/>
<lowest/>
<highest/>
<netvalue/>
<openamount/>
<openinterest/>
<amount/>
<point/>
<positiontime>3</positiontime>
<memo>TRMM-DP(123005)-D</memo>
</record>
<record>
<pono>5011083</pono>
<status>3</status>
<opentime>2010.06.15 16:15</opentime>
<closetime>2010.06.15 16:23</closetime>
<potype>buy</potype>
<variety>eurusd</variety>
<margin/>
<openprice>1.31822</openprice>
<closeprice>1.31655</closeprice>
<zhisun>0</zhisun>
<zhiying>0</zhiying>
<lowest/>
<highest/>
<netvalue/>
<openamount/>
<openinterest/>
<amount/>
<point/>
<positiontime>00:08:00</positiontime>
<memo>aaafff</memo>
</record>
<record>
<pono>5011913</pono>
<status>3</status>
<opentime>2010.06.15 16:51</opentime>
<closetime>2010.06.15 17:19</closetime>
<potype>sell</potype>
<variety>eurusd</variety>
<margin/>
<openprice>1.31819</openprice>
<closeprice>1.31809</closeprice>
<zhisun>0</zhisun>
<zhiying>0</zhiying>
<lowest/>
<highest/>
<netvalue/>
<openamount/>
<openinterest/>
<amount/>
<point/>
<positiontime>00:28:00</positiontime>
<memo>eee</memo>
</record>
</records>
php文件里的处理。
$file ="mainchart.xml";
//创建DOMDocument的对象
$dom=new DOMDocument('1.0');
//载入mainchart.xml文件
$dom->load($file);
//获得record节点的集合
$records = $dom->getElementsByTagName('record');
//遍历record节点的集合
foreach($records as $record){
//如果record节点的pono子节点的值满足条件，就修改该record节点下memo子节点的值
if($record->getElementsByTagName('pono')->item(0)->nodeValue == $_GET['id']){
$record->getElementsByTagName('memo')->item(0)->nodeValue = $_GET['content'];
}
}
$dom->save('mainchart.xml');
$_GET['id']和$_GET['content']是ajax传过来的参数。