如何：查找子元素列表 (XPath-LINQ to XML)

更新：November 2007

本主题将 XPath 子元素轴与 LINQ to XML Elements 轴进行比较。

XPath 表达式为：./*

示例

本示例查找 Address 元素的所有子元素。

本示例使用下面的 XML 文档：示例 XML 文件：多个采购订单 (LINQ to XML)。

XDocument cpo = XDocument.Load("PurchaseOrders.xml");
XElement po = cpo.Root.Element("PurchaseOrder").Element("Address");

// LINQ to XML query
IEnumerable<XElement> list1 = po.Elements();

// XPath expression
IEnumerable<XElement> list2 = po.XPathSelectElements("./*");

if (list1.Count() == list2.Count() &&
        list1.Intersect(list2).Count() == list1.Count())
    Console.WriteLine("Results are identical");
else
    Console.WriteLine("Results differ");
foreach (XElement el in list1)
    Console.WriteLine(el);

Dim cpo As XDocument = XDocument.Load("PurchaseOrders.xml")
Dim po As XElement = cpo.Root.<PurchaseOrder>.<Address>.FirstOrDefault

' LINQ to XML query
Dim list1 As IEnumerable(Of XElement) = po.Elements()

' XPath expression
Dim list2 As IEnumerable(Of XElement) = po.XPathSelectElements("./*")

If (list1.Count() = list2.Count()) AndAlso _
    (list1.Intersect(list2).Count() = list1.Count()) Then
    Console.WriteLine("Results are identical")
Else
    Console.WriteLine("Results differ")
End If
For Each el As XElement In list1
    Console.WriteLine(el)
Next

本示例生成以下输出：

Results are identical
<Name>Ellen Adams</Name>
<Street>123 Maple Street</Street>
<City>Mill Valley</City>
<State>CA</State>
<Zip>10999</Zip>
<Country>USA</Country>

请参见

概念

针对 XPath 用户的 LINQ to XML