C# 如何移除xml文档中的所有命名空间

using System.Xml.Linq;

public static XDocument RemoveAllNamespaces(XDocument doc)
{
    var stripped = new XDocument();
    stripped.Add(RemoveNamespacesInElement(doc.Root));
    return stripped;
}

private static XElement RemoveNamespacesInElement(XElement element)
{
    var cleaned = new XElement(element.Name.LocalName);

    // 复制所有属性（不带命名空间）
    foreach (var attr in element.Attributes().Where(a => !a.IsNamespaceDeclaration))
    {
        cleaned.Add(new XAttribute(attr.Name.LocalName, attr.Value));
    }

    // 复制子节点：文本或嵌套元素
    foreach (var node in element.Nodes())
    {
        if (node is XElement subElement)
        {
            cleaned.Add(RemoveNamespacesInElement(subElement));
        }
        else
        {
            cleaned.Add(node);
        }
    }

    return cleaned;
}

<?xml version="1.0" encoding="utf-8"?>
<root xmlns:ns1="http://example.com/ns1" xmlns:ns2="http://example.com/ns2">
  <ns1:item id="1">Value 1</ns1:item>
  <ns2:item id="2">Value 2</ns2:item>
</root>

<?xml version="1.0" encoding="utf-8"?>
<root>
  <item id="1">Value 1</item>
  <item id="2">Value 2</item>
</root>