为什么我必须将空名称空间传递给XPathNavigator.GetAttribute？(Why do I have to pass an empty namespace to XPathNavigat

为什么我必须将空名称空间传递给XPathNavigator.GetAttribute？(Why do I have to pass an empty namespace to XPathNavigator.GetAttribute?)

给定以下XML标记：

<root xmlns="Demo"> <child name="foo"/> </root>

和一个位于<child>元素上的XPathNavigator ，

string withNs = navigator.GetAttribute("name", navigator.NamespaceURI); string withoutNs = navigator.GetAttribute("name", "");

产生奇怪的结果： withNs是空的，没有withoutNs包含foo 。

这是为什么？ 我原以为它会反过来，因为name属性必须在Demo命名空间中，就像child元素一样。

MSDN文档没有提到传递namespaceURI=""任何神奇含义，所以我假设您必须传递属性的真实名称空间URI。

Given the following XML markup:

<root xmlns="Demo"> <child name="foo"/> </root>

and an XPathNavigator positioned on the <child> element,

string withNs = navigator.GetAttribute("name", navigator.NamespaceURI); string withoutNs = navigator.GetAttribute("name", "");

produce strange results: withNs is empty, withoutNs contains foo.

Why is that? I would have expected it would be the other way round, as the name attribute must be in the Demo namespace like the child element.

The MSDN documentation does not mention any magic meaning of passing namespaceURI="", so I assumed you have to pass the real namespace URI of the attribute.

最满意答案

因为name属性必须在Demo命名空间中，就像child元素一样。

根据w3c规范，属性不会继承它们所属元素的命名空间，这就是为什么你得到那些正确的结果的原因。

相关文章： http ： //web.archive.org/web/20170118162309/http : //www.xmlplease.com/attributexmlns

as the name attribute must be in the Demo namespace like the child element.

Attributes do not inherit the namespace of the element to which they belong, as per the w3c specification, and that is why you got those results, which are correct.

Related article: http://web.archive.org/web/20170118162309/http://www.xmlplease.com/attributexmlns