Extensions.Elements Method

Definition

傳回來源集合中每個項目和文件的子項目集合。Returns a collection of the child elements of every element and document in the source collection.

Overloads

Elements<T>(IEnumerable<T>)

傳回來源集合中每個項目和文件的子項目集合。Returns a collection of the child elements of every element and document in the source collection.

Elements<T>(IEnumerable<T>, XName)

傳回來源集合中每個項目和文件的已篩選子項目集合。Returns a filtered collection of the child elements of every element and document in the source collection. 集合中只會包含具有相符之 XName 的項目。Only elements that have a matching XName are included in the collection.

Remarks

Visual Basic 包含整合式元素軸,可讓您尋找來源集合中每個專案具有指定 XName 的所有子專案。Visual Basic contains an integrated elements axis that allows you to find all child elements with a specified XName for every element in the source collection.

這個方法會使用延後的執行。This method uses deferred execution.

Elements<T>(IEnumerable<T>)

傳回來源集合中每個項目和文件的子項目集合。Returns a collection of the child elements of every element and document in the source collection.

public:
generic <typename T>
 where T : System::Xml::Linq::XContainer[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::IEnumerable<System::Xml::Linq::XElement ^> ^ Elements(System::Collections::Generic::IEnumerable<T> ^ source);
public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Elements<T> (this System.Collections.Generic.IEnumerable<T> source) where T : System.Xml.Linq.XContainer;
static member Elements : seq<'T (requires 'T :> System.Xml.Linq.XContainer)> -> seq<System.Xml.Linq.XElement> (requires 'T :> System.Xml.Linq.XContainer)
<Extension()>
Public Function Elements(Of T As XContainer) (source As IEnumerable(Of T)) As IEnumerable(Of XElement)

Type Parameters

T

source 中物件的型別,限制為 XContainerThe type of the objects in source, constrained to XContainer.

Parameters

source
IEnumerable<T>

IEnumerable<T>XElement,其中包含來源集合。An IEnumerable<T> of XElement that contains the source collection.

Returns

IEnumerable<XElement>

來源集合中每個項目或文件的子項目之 IEnumerable<T>XElementAn IEnumerable<T> of XElement of the child elements of every element or document in the source collection.

Examples

下列範例會抓取專案名稱為 Child的元素集合。The following example retrieves a collection of elements with the element name of Child. 然後,它會使用此 axis 方法來抓取集合的所有子專案。It then uses this axis method to retrieve all child elements of the collection.

XElement xmlTree = new XElement("Root",  
    new XElement("Child",  
        new XElement("GrandChild1", 1),  
        new XElement("GrandChild2", 2)  
    ),  
    new XElement("Child",  
        new XElement("GrandChild3", 3),  
        new XElement("GrandChild4", 4)  
    ),  
    new XElement("Child",  
        new XElement("GrandChild5", 5),  
        new XElement("GrandChild6", 6)  
    )  
);  
  
IEnumerable<XElement> allGrandChildren =  
    from el in xmlTree.Elements("Child").Elements()  
    select el;  
  
foreach (XElement el in allGrandChildren)  
    Console.WriteLine(el);  
Dim xmlTree As XElement = _  
     <Root>  
          <Child>  
              <GrandChild1>1</GrandChild1>  
              <GrandChild2>2</GrandChild2>  
          </Child>  
  
          <Child>  
              <GrandChild3>3</GrandChild3>  
              <GrandChild4>4</GrandChild4>  
          </Child>  
  
          <Child>  
              <GrandChild5>5</GrandChild5>  
              <GrandChild6>6</GrandChild6>  
          </Child>  
      </Root>  
  
Dim allGrandChildren = From el In xmlTree.<Child>.Elements _  
                       Select el  
  
For Each el As XElement In allGrandChildren  
    Console.WriteLine(el)  
Next  
  

這個範例會產生下列輸出:This example produces the following output:

<GrandChild1>1</GrandChild1>  
<GrandChild2>2</GrandChild2>  
<GrandChild3>3</GrandChild3>  
<GrandChild4>4</GrandChild4>  
<GrandChild5>5</GrandChild5>  
<GrandChild6>6</GrandChild6>  

下列是相同的範例,但在此情況下,XML 是在命名空間中。The following is the same example, but in this case the XML is in a namespace. 如需詳細資訊,請參閱使用 XML 命名空間For more information, see Working with XML Namespaces.

XNamespace aw = "http://www.adventure-works.com";  
XElement xmlTree = new XElement(aw + "Root",  
    new XElement(aw + "Child",  
        new XElement(aw + "GrandChild1", 1),  
        new XElement(aw + "GrandChild2", 2)  
    ),  
    new XElement(aw + "Child",  
        new XElement(aw + "GrandChild3", 3),  
        new XElement(aw + "GrandChild4", 4)  
    ),  
    new XElement(aw + "Child",  
        new XElement(aw + "GrandChild5", 5),  
        new XElement(aw + "GrandChild6", 6)  
    )  
);  
  
IEnumerable<XElement> allGrandChildren =  
    from el in xmlTree.Elements(aw + "Child").Elements()  
    select el;  
  
foreach (XElement el in allGrandChildren)  
    Console.WriteLine(el);  
Imports <xmlns="http://www.adventure-works.com">  
  
Module Module1  
    Sub Main()  
        Dim xmlTree As XElement = _  
             <Root>  
                 <Child>  
                     <GrandChild1>1</GrandChild1>  
                     <GrandChild2>2</GrandChild2>  
                 </Child>  
  
                 <Child>  
                     <GrandChild3>3</GrandChild3>  
                     <GrandChild4>4</GrandChild4>  
                 </Child>  
  
                 <Child>  
                     <GrandChild5>5</GrandChild5>  
                     <GrandChild6>6</GrandChild6>  
                 </Child>  
             </Root>  
  
        Dim allGrandChildren = From el In xmlTree.<Child>.Elements _  
                               Select el  
  
        For Each el As XElement In allGrandChildren  
            Console.WriteLine(el)  
        Next  
    End Sub  
End Module  
  

這個範例會產生下列輸出:This example produces the following output:

<GrandChild1 xmlns="http://www.adventure-works.com">1</GrandChild1>  
<GrandChild2 xmlns="http://www.adventure-works.com">2</GrandChild2>  
<GrandChild3 xmlns="http://www.adventure-works.com">3</GrandChild3>  
<GrandChild4 xmlns="http://www.adventure-works.com">4</GrandChild4>  
<GrandChild5 xmlns="http://www.adventure-works.com">5</GrandChild5>  
<GrandChild6 xmlns="http://www.adventure-works.com">6</GrandChild6>  

Remarks

雖然 Visual Basic 包含整合式專案軸,可讓您針對來源集合中的每個元素,尋找具有指定 XName 的所有子專案,但沒有整合的元素軸可讓您針對來源集合中的每個專案,抓取每個子專案的集合。Although Visual Basic contains an integrated elements axis that allows you to find all child elements with a specified XName for every element in the source collection, there is no integrated elements axis that allows you to retrieve a collection of every child element for every element in the source collection.

這個方法會使用延後的執行。This method uses deferred execution.

See also

Elements<T>(IEnumerable<T>, XName)

傳回來源集合中每個項目和文件的已篩選子項目集合。Returns a filtered collection of the child elements of every element and document in the source collection. 集合中只會包含具有相符之 XName 的項目。Only elements that have a matching XName are included in the collection.

public:
generic <typename T>
 where T : System::Xml::Linq::XContainer[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::IEnumerable<System::Xml::Linq::XElement ^> ^ Elements(System::Collections::Generic::IEnumerable<T> ^ source, System::Xml::Linq::XName ^ name);
public static System.Collections.Generic.IEnumerable<System.Xml.Linq.XElement> Elements<T> (this System.Collections.Generic.IEnumerable<T> source, System.Xml.Linq.XName name) where T : System.Xml.Linq.XContainer;
static member Elements : seq<'T (requires 'T :> System.Xml.Linq.XContainer)> * System.Xml.Linq.XName -> seq<System.Xml.Linq.XElement> (requires 'T :> System.Xml.Linq.XContainer)
<Extension()>
Public Function Elements(Of T As XContainer) (source As IEnumerable(Of T), name As XName) As IEnumerable(Of XElement)

Type Parameters

T

source 中物件的型別,限制為 XContainerThe type of the objects in source, constrained to XContainer.

Parameters

source
IEnumerable<T>

IEnumerable<T>XElement,其中包含來源集合。An IEnumerable<T> of XElement that contains the source collection.

name
XName

要比對的 XNameThe XName to match.

Returns

IEnumerable<XElement>

來源集合中每個項目和文件之 IEnumerable<T>XElementAn IEnumerable<T> of XElement of the child elements of every element and document in the source collection. 集合中只會包含具有相符之 XName 的項目。Only elements that have a matching XName are included in the collection.

Examples

當您想要取得特定深度的所有具有指定名稱的元素時,這個擴充方法會很有用。This extension method is useful when you want to retrieve all elements with a specified name at a particular depth. 如果檔非常一般,這很簡單,但如果檔異常,可能會比較困難。This is easy if the document is very regular, but if the document is irregular, it can be a bit more difficult. 在下列範例中,我們想要取出 Item 專案子系的所有 aaa 專案。In the following example, we want to retrieve all aaa elements that are children of Item elements. 給定的 Item 元素不一定包含 aaa 元素。A given Item element may or may not contain an aaa element. 這可使用此擴充方法輕鬆完成,如下所示:This is easily accomplished using this extension method, as follows:

XElement xmlTree = new XElement("Root",  
    new XElement("Item",  
        new XElement("aaa", 1),  
        new XElement("bbb", 2)  
    ),  
    new XElement("Item",  
        new XElement("ccc", 3),  
        new XElement("aaa", 4)  
    ),  
    new XElement("Item",  
        new XElement("ddd", 5),  
        new XElement("eee", 6)  
    )  
);  
  
IEnumerable<XElement> allGrandChildren =  
    from el in xmlTree.Elements("Item").Elements("aaa")  
    select el;  
  
foreach (XElement el in allGrandChildren)  
    Console.WriteLine(el);  
Dim xmlTree As XElement = _  
    <Root>  
        <Item>  
            <aaa>1</aaa>  
            <bbb>2</bbb>  
        </Item>  
  
        <Item>  
            <ccc>3</ccc>  
            <aaa>4</aaa>  
        </Item>  
  
        <Item>  
            <ddd>5</ddd>  
            <eee>6</eee>  
        </Item>  
    </Root>  
  
Dim allGrandChildren = From el In xmlTree.<Item>.<aaa> _  
                       Select el  
  
For Each el As XElement In allGrandChildren  
    Console.WriteLine(el)  
Next  
  

這個範例會產生下列輸出:This example produces the following output:

<aaa>1</aaa>  
<aaa>4</aaa>  

下列是相同的範例,但在此情況下,XML 是在命名空間中。The following is the same example, but in this case the XML is in a namespace. 如需詳細資訊,請參閱使用 XML 命名空間For more information, see Working with XML Namespaces.

XNamespace aw = "http://www.adventure-works.com";  
XElement xmlTree = new XElement(aw + "Root",  
    new XElement(aw + "Item",  
        new XElement(aw + "aaa", 1),  
        new XElement(aw + "bbb", 2)  
    ),  
    new XElement(aw + "Item",  
        new XElement(aw + "ccc", 3),  
        new XElement(aw + "aaa", 4)  
    ),  
    new XElement(aw + "Item",  
        new XElement(aw + "ddd", 5),  
        new XElement(aw + "eee", 6)  
    )  
);  
  
IEnumerable<XElement> allGrandChildren =  
    from el in xmlTree.Elements(aw + "Item").Elements(aw + "aaa")  
    select el;  
  
foreach (XElement el in allGrandChildren)  
    Console.WriteLine(el);  
Imports <xmlns="http://www.adventure-works.com">  
  
Module Module1  
    Sub Main()  
        Dim xmlTree As XElement = _  
            <Root>  
                <Item>  
                    <aaa>1</aaa>  
                    <bbb>2</bbb>  
                </Item>  
  
                <Item>  
                    <ccc>3</ccc>  
                    <aaa>4</aaa>  
                </Item>  
  
                <Item>  
                    <ddd>5</ddd>  
                    <eee>6</eee>  
                </Item>  
            </Root>  
  
        Dim allGrandChildren = From el In xmlTree.<Item>.<aaa> _  
                               Select el  
  
        For Each el As XElement In allGrandChildren  
            Console.WriteLine(el)  
        Next  
    End Sub  
End Module  
  

這個範例會產生下列輸出:This example produces the following output:

<aaa xmlns="http://www.adventure-works.com">1</aaa>  
<aaa xmlns="http://www.adventure-works.com">4</aaa>  

Remarks

Visual Basic 使用者可以使用 [整合專案] 軸來抓取集合中每個專案的子項目。Visual Basic users can use the integrated elements axis to retrieve the child elements of every element in a collection.

這個方法會使用延後的執行。This method uses deferred execution.

See also

Applies to