使用 SelectSingleNode 获取属性值

Using SelectSingleNode to get an attribute value

我想使用 SelectSingleNode 获取节点的属性值。我已经检查过 here.

我已经尝试过这些选择器,但它们 return 是空引用异常: node.SelectSingleNode("/@id").InnerText node.SelectSingleNode("@id").InnerText

这是我正在尝试解析的 XML 的一部分:

<?xml version="1.0" encoding="utf-8"?>
    <products>
        <product ID="4de">
            <name>Prod name</name>
        </product>
        <product ID="4dea">
            <name>Prod name 2</name>
        </product>      
</products>


Dim productXML As New XmlDocument
Dim node As XmlNode
Dim root As XmlNode
productXML.LoadXml(responseString)
Dim mgr As XmlNamespaceManager = New XmlNamespaceManager(productXML.NameTable)
mgr.AddNamespace("test", productXML.DocumentElement.NamespaceURI)

root = productXML.DocumentElement
Dim nodeList As XmlNodeList = root.SelectNodes("/products/product")

'to get the product title (this works): 
node.SelectSingleNode("name").InnerText

如何通过SelectSingleNode获取product节点的'ID'属性值?

请注意 XML 区分大小写,因此您应该使用大写 @ID 来代替:

node.SelectSingleNode("@ID").InnerText

演示(在 C# 中):https://dotnetfiddle.net/TWMUlD

var xml = @" <products>
        <product ID='4de'>
            <name>Prod name</name>
        </product>
        <product ID='4dea'>
            <name>Prod name 2</name>
        </product>      
</products>";
var root = new XmlDocument();
root.LoadXml(xml);
var nodeList = root.SelectNodes("/products/product");
foreach (XmlNode node in nodeList)
{
    var id = node.SelectSingleNode("@ID").InnerText;
    Console.WriteLine(id);
}

输出:

4de
4dea