我正在编写一个读取和操作 KML (xml) 文档的脚本。以下是我正在阅读的文档的片段:
<?xml version="1.0" encoding="UTF-8"?>
<!-- Generated by Feature Manipulation Engine 2009 (Build 5658) -->
<kml xmlns="http://earth.google.com/kml/2.2" xmlns:atom="http://www.w3.org/2005/Atom">
<Document>
<name>South Australia</name>
<visibility>1</visibility>
<description><![CDATA[Statistical Local Area 2008]]></description>
<Folder id="kml_ft_SA_SLA08">
<name>SA_SLA08</name>
<Placemark id="kml_1">
<name>Mitcham (C) - West</name>
<Style>
<!-- style info blah blah -->
</Style>
<Polygon>
<!-- blah blah -->
</Polygon>
</Placemark>
<!-- snip lots more Placemarks -->
</Folder>
</Document>
</kml>
我遇到的问题是使用 XPath 从中选择任何内容!
$doc = new DOMDocument();
$doc->load('myfile.xml'); // returns true
$xp = new DOMXPath($doc);
$places = $xp->query("//Placemark");
echo $places->length; // --> 0 ??!!??
$everything = $xp->query("//*"); // (so I know that the XPath isn't fully borked)
echo $everything->length; // --> 2085
这里发生了什么?