Extensions.Ancestors 方法
定义
重要
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返回元素集合,其中包含源集合中每个节点的上级。
重载
Ancestors<T>(IEnumerable<T>) |
返回元素集合,其中包含源集合中每个节点的上级。 |
Ancestors<T>(IEnumerable<T>, XName) |
返回经过筛选的元素集合,其中包含源集合中每个节点的上级。 集合中仅包括具有匹配 XName 的元素。 |
注解
如果源集合中的多个节点具有相同的上级,则上级将多次包含在结果集合中。 若要避免这种情况,请使用 Distinct 该方法。
此方法使用延迟执行。
Ancestors<T>(IEnumerable<T>)
返回元素集合,其中包含源集合中每个节点的上级。
public:
generic <typename T>
where T : System::Xml::Linq::XNode[System::Runtime::CompilerServices::Extension]
static System::Collections::Generic::IEnumerable<System::Xml::Linq::XElement ^> ^ Ancestors(System::Collections::Generic::IEnumerable<T> ^ source);
public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T> source) where T : System.Xml.Linq.XNode;
public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T?> source) where T : System.Xml.Linq.XNode;
static member Ancestors : seq<'T (requires 'T :> System.Xml.Linq.XNode)> -> seq<System.Xml.Linq.XElement> (requires 'T :> System.Xml.Linq.XNode)
<Extension()>
Public Function Ancestors(Of T As XNode) (source As IEnumerable(Of T)) As IEnumerable(Of XElement)
类型参数
- T
source
中对象的类型,被约束为 XNode。
参数
- source
- IEnumerable<T>
一个包含源集合的 IEnumerable<T> 的 XNode。
返回
一个包含源集合中每个节点的上级的 IEnumerable<T> 的 XElement。
示例
以下示例检索大孙子元素的集合。 然后,它使用此轴方法检索集合中所有元素的所有上级。
XElement xmlTree = new XElement("Root",
new XElement("Child1",
new XElement("GrandChild1",
new XElement("GreatGrandChild1", "content")
)
),
new XElement("Child2",
new XElement("GrandChild2",
new XElement("GreatGrandChild2", "content")
)
)
);
IEnumerable<XElement> greatGrandChildren =
from el in xmlTree.Descendants()
where el.Name.LocalName.StartsWith("Great")
select el;
Console.WriteLine("Great Grand Children Elements");
Console.WriteLine("----");
foreach (XElement de in greatGrandChildren)
Console.WriteLine(de.Name);
IEnumerable<XElement> allAncestors =
from el in greatGrandChildren.Ancestors().Distinct()
select el;
Console.WriteLine("");
Console.WriteLine("Ancestors");
Console.WriteLine("----");
foreach (XElement de in allAncestors)
Console.WriteLine(de.Name);
Dim xmlTree As XElement = _
<Root>
<Child1>
<GrandChild1>
<GreatGrandChild1>content</GreatGrandChild1>
</GrandChild1>
</Child1>
<Child2>
<GrandChild2>
<GreatGrandChild2>content</GreatGrandChild2>
</GrandChild2>
</Child2>
</Root>
Dim greatGrandChildren = From el In xmlTree.Descendants _
Where el.Name.LocalName.StartsWith("Great") _
Select el
Console.WriteLine("Great Grand Children Elements")
Console.WriteLine("----")
For Each de As XElement In greatGrandChildren
Console.WriteLine(de.Name)
Next
Dim allAncestors = From el In greatGrandChildren.Ancestors.Distinct _
Select el
Console.WriteLine("")
Console.WriteLine("Ancestors")
Console.WriteLine("----")
For Each de As XElement In allAncestors
Console.WriteLine(de.Name)
Next
该示例产生下面的输出:
Great Grand Children Elements
----
GreatGrandChild1
GreatGrandChild2
Ancestors
----
GrandChild1
Child1
Root
GrandChild2
Child2
以下示例相同,但在这种情况下,XML 位于命名空间中。 有关详细信息,请参阅 使用 XML 命名空间。
XNamespace aw = "http://www.adventure-works.com";
XElement xmlTree = new XElement(aw + "Root",
new XElement(aw + "Child1",
new XElement(aw + "GrandChild1",
new XElement(aw + "GreatGrandChild1", "content")
)
),
new XElement(aw + "Child2",
new XElement(aw + "GrandChild2",
new XElement(aw + "GreatGrandChild2", "content")
)
)
);
IEnumerable<XElement> greatGrandChildren =
from el in xmlTree.Descendants()
where el.Name.LocalName.StartsWith("Great")
select el;
Console.WriteLine("Great Grand Children Elements");
Console.WriteLine("----");
foreach (XElement de in greatGrandChildren)
Console.WriteLine(de.Name);
IEnumerable<XElement> allAncestors =
from el in greatGrandChildren.Ancestors().Distinct()
select el;
Console.WriteLine("");
Console.WriteLine("Ancestors");
Console.WriteLine("----");
foreach (XElement de in allAncestors)
Console.WriteLine(de.Name);
Imports <xmlns="http://www.adventure-works.com">
Module Module1
Sub Main()
Dim xmlTree As XElement = _
<Root>
<Child1>
<GrandChild1>
<GreatGrandChild1>content</GreatGrandChild1>
</GrandChild1>
</Child1>
<Child2>
<GrandChild2>
<GreatGrandChild2>content</GreatGrandChild2>
</GrandChild2>
</Child2>
</Root>
Dim greatGrandChildren = From el In xmlTree.Descendants _
Where el.Name.LocalName.StartsWith("Great") _
Select el
Console.WriteLine("Great Grand Children Elements")
Console.WriteLine("----")
For Each de As XElement In greatGrandChildren
Console.WriteLine(de.Name)
Next
Dim allAncestors = From el In greatGrandChildren.Ancestors.Distinct _
Select el
Console.WriteLine("")
Console.WriteLine("Ancestors")
Console.WriteLine("----")
For Each de As XElement In allAncestors
Console.WriteLine(de.Name)
Next
End Sub
End Module
该示例产生下面的输出:
Great Grand Children Elements
----
{http://www.adventure-works.com}GreatGrandChild1
{http://www.adventure-works.com}GreatGrandChild2
Ancestors
----
{http://www.adventure-works.com}GrandChild1
{http://www.adventure-works.com}Child1
{http://www.adventure-works.com}Root
{http://www.adventure-works.com}GrandChild2
{http://www.adventure-works.com}Child2
注解
如果源集合中的多个节点具有相同的上级,则上级将多次包含在结果集合中。 若要避免这种情况,请使用 Distinct 该方法。
此方法使用延迟执行。
另请参阅
适用于
Ancestors<T>(IEnumerable<T>, XName)
返回经过筛选的元素集合,其中包含源集合中每个节点的上级。 集合中仅包括具有匹配 XName 的元素。
public:
generic <typename T>
where T : System::Xml::Linq::XNode[System::Runtime::CompilerServices::Extension]
static System::Collections::Generic::IEnumerable<System::Xml::Linq::XElement ^> ^ Ancestors(System::Collections::Generic::IEnumerable<T> ^ source, System::Xml::Linq::XName ^ name);
public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T> source, System.Xml.Linq.XName name) where T : System.Xml.Linq.XNode;
public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Ancestors<T> (this System.Collections.Generic.IEnumerable<T?> source, System.Xml.Linq.XName? name) where T : System.Xml.Linq.XNode;
static member Ancestors : seq<'T (requires 'T :> System.Xml.Linq.XNode)> * System.Xml.Linq.XName -> seq<System.Xml.Linq.XElement> (requires 'T :> System.Xml.Linq.XNode)
<Extension()>
Public Function Ancestors(Of T As XNode) (source As IEnumerable(Of T), name As XName) As IEnumerable(Of XElement)
类型参数
- T
source
中对象的类型,被约束为 XNode。
参数
- source
- IEnumerable<T>
一个包含源集合的 IEnumerable<T> 的 XNode。
返回
一个包含源集合中每个节点的上级的 IEnumerable<T> 的 XElement。 集合中仅包括具有匹配 XName 的元素。
示例
以下示例检索大孙子元素的集合。 然后,它使用此轴方法检索集合中与指定 XName元素匹配的所有元素的所有上级。
XElement xmlTree = new XElement("Root",
new XElement("Child1",
new XElement("GrandChild1",
new XElement("GreatGrandChild1", "content")
)
),
new XElement("Child2",
new XElement("GrandChild2",
new XElement("GreatGrandChild2", "content")
)
)
);
IEnumerable<XElement> greatGrandChildren =
from el in xmlTree.Descendants()
where el.Name.LocalName.StartsWith("Great")
select el;
Console.WriteLine("Great Grand Children Elements");
Console.WriteLine("----");
foreach (XElement de in greatGrandChildren)
Console.WriteLine(de.Name);
IEnumerable<XElement> allAncestors =
from el in greatGrandChildren.Ancestors("Child1")
select el;
Console.WriteLine("");
Console.WriteLine("Ancestors");
Console.WriteLine("----");
foreach (XElement de in allAncestors)
Console.WriteLine(de.Name);
Dim xmlTree As XElement = _
<Root>
<Child1>
<GrandChild1>
<GreatGrandChild1>content</GreatGrandChild1>
</GrandChild1>
</Child1>
<Child2>
<GrandChild2>
<GreatGrandChild2>content</GreatGrandChild2>
</GrandChild2>
</Child2>
</Root>
Dim greatGrandChildren = From el In xmlTree.Descendants _
Where el.Name.LocalName.StartsWith("Great") _
Select el
Console.WriteLine("Great Grand Children Elements")
Console.WriteLine("----")
For Each de As XElement In greatGrandChildren
Console.WriteLine(de.Name)
Next
Dim allAncestors = From el In greatGrandChildren.Ancestors("Child1") _
Select el
Console.WriteLine("")
Console.WriteLine("Ancestors")
Console.WriteLine("----")
For Each de As XElement In allAncestors
Console.WriteLine(de.Name)
Next
该示例产生下面的输出:
Great Grand Children Elements
----
GreatGrandChild1
GreatGrandChild2
Ancestors
----
Child1
以下示例相同,但在这种情况下,XML 位于命名空间中。 有关详细信息,请参阅 使用 XML 命名空间。
XNamespace aw = "http://www.adventure-works.com";
XElement xmlTree = new XElement(aw + "Root",
new XElement(aw + "Child1",
new XElement(aw + "GrandChild1",
new XElement(aw + "GreatGrandChild1", "content")
)
),
new XElement(aw + "Child2",
new XElement(aw + "GrandChild2",
new XElement(aw + "GreatGrandChild2", "content")
)
)
);
IEnumerable<XElement> greatGrandChildren =
from el in xmlTree.Descendants()
where el.Name.LocalName.StartsWith("Great")
select el;
Console.WriteLine("Great Grand Children Elements");
Console.WriteLine("----");
foreach (XElement de in greatGrandChildren)
Console.WriteLine(de.Name);
IEnumerable<XElement> allAncestors =
from el in greatGrandChildren.Ancestors(aw + "Child1")
select el;
Console.WriteLine("");
Console.WriteLine("Ancestors");
Console.WriteLine("----");
foreach (XElement de in allAncestors)
Console.WriteLine(de.Name);
Imports <xmlns="http://www.adventure-works.com">
Module Module1
Sub Main()
Dim xmlTree As XElement = _
<Root>
<Child1>
<GrandChild1>
<GreatGrandChild1>content</GreatGrandChild1>
</GrandChild1>
</Child1>
<Child2>
<GrandChild2>
<GreatGrandChild2>content</GreatGrandChild2>
</GrandChild2>
</Child2>
</Root>
Dim greatGrandChildren = From el In xmlTree.Descendants _
Where el.Name.LocalName.StartsWith("Great") _
Select el
Console.WriteLine("Great Grand Children Elements")
Console.WriteLine("----")
For Each de As XElement In greatGrandChildren
Console.WriteLine(de.Name)
Next
Dim allAncestors = From el In greatGrandChildren.Ancestors(GetXmlNamespace() + "Child1") _
Select el
Console.WriteLine("")
Console.WriteLine("Ancestors")
Console.WriteLine("----")
For Each de As XElement In allAncestors
Console.WriteLine(de.Name)
Next
End Sub
End Module
该示例产生下面的输出:
Great Grand Children Elements
----
{http://www.adventure-works.com}GreatGrandChild1
{http://www.adventure-works.com}GreatGrandChild2
Ancestors
----
{http://www.adventure-works.com}Child1
注解
如果源集合中的多个节点具有相同的上级与匹配 XName,则上级将多次包含在结果集合中。
此方法使用延迟执行。