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XElement Constructors

  • Reference

Definition

Namespace:
System.Xml.Linq
Assembly:
System.Xml.XDocument.dll
Assembly:
System.Xml.Linq.dll
Assembly:
netstandard.dll

Initializes a new instance of the XElement class.

Overloads

XElement(XElement)

Initializes a new instance of the XElement class from another XElement object.
XElement(XName)

Initializes a new instance of the XElement class with the specified name.
XElement(XStreamingElement)

Initializes a new instance of the XElement class from an XStreamingElement object.
XElement(XName, Object)

Initializes a new instance of the XElement class with the specified name and content.
XElement(XName, Object[])

Initializes a new instance of the XElement class with the specified name and content.

Examples

The following example creates an XML tree. The content of the new element comes from a LINQ query.

XElement xmlTree1 = new XElement("Root",
    new XElement("Child", 1),
    new XElement("Child", 2),
    new XElement("Child", 3),
    new XElement("Child", 4),
    new XElement("Child", 5),
    new XElement("Child", 6)
);

XElement xmlTree2 = new XElement("Root",
    from el in xmlTree1.Elements()
    where((int)el >= 3 && (int)el <= 5)
    select el
);
Console.WriteLine(xmlTree2);

Dim xmlTree1 As XElement = _
        <Root>
            <Child>1</Child>
            <Child>2</Child>
            <Child>3</Child>
            <Child>4</Child>
            <Child>5</Child>
            <Child>6</Child>
        </Root>

Dim xmlTree2 As XElement = _
    <Root>
        <%= From el In xmlTree1.Elements() _
            Where el.Value >= 3 And el.Value <= 5 _
            Select el %>
    </Root>

Console.WriteLine(xmlTree2)

This example produces the following output:

<Root>
  <Child>3</Child>
  <Child>4</Child>
  <Child>5</Child>
</Root>

Remarks

For details about the valid content that can be passed to this constructor, see Valid Content of XElement and XDocument Objects.

There is an implicit conversion from string to XName. Typical use of this constructor is to specify a string as the parameter instead of creating a new XName.

When creating an element in a namespace, typical use is to use the addition operator overload with an XNamespace and a string to create an XName. For more information, see Work with XML Namespaces.

XElement(XElement)

Source:
XElement.cs
Source:
XElement.cs
Source:
XElement.cs

Initializes a new instance of the XElement class from another XElement object.

public:
 XElement(System::Xml::Linq::XElement ^ other);
public XElement (System.Xml.Linq.XElement other);
new System.Xml.Linq.XElement : System.Xml.Linq.XElement -> System.Xml.Linq.XElement
Public Sub New (other As XElement)

Parameters

other
XElement

An XElement object to copy from.

Examples

The following example creates an XML tree, creates a clone of the tree, and then calls DeepEquals, which tests whether the two XML trees are equal.

XElement xmlTree = new XElement("Root",
    new XAttribute("Att1", 1),
    new XElement("Child1", 1),
    new XElement("Child2", 2)
);

// Create a clone of the tree.
XElement treeClone = new XElement(xmlTree);

Console.WriteLine("xmlTree = treeClone: {0}", XNode.DeepEquals(xmlTree, treeClone));

// Do some work with xmlTree, perhaps pass it to other methods.
xmlTree.Add(new XElement("Child3", 3));

Console.WriteLine("xmlTree = treeClone: {0}", XNode.DeepEquals(xmlTree, treeClone));

Dim xmlTree As XElement = _
        <Root Att1="1">
            <Child1>1</Child1>
            <Child2>2</Child2>
        </Root>

' Create a clone of the tree.
Dim treeClone As XElement = New XElement(xmlTree)

Console.WriteLine("xmlTree = treeClone: {0}", XNode.DeepEquals(xmlTree, treeClone))

' Do some work with xmlTree, perhaps pass it to other methods.
xmlTree.Add(New XElement("Child3", 3))

Console.WriteLine("xmlTree = treeClone: {0}", XNode.DeepEquals(xmlTree, treeClone))

This example produces the following output:

xmlTree = treeClone: True
xmlTree = treeClone: False

Remarks

This constructor makes a deep copy of an element.

See also

Applies to

XElement(XName)

Source:
XElement.cs
Source:
XElement.cs
Source:
XElement.cs

Initializes a new instance of the XElement class with the specified name.

public:
 XElement(System::Xml::Linq::XName ^ name);
public XElement (System.Xml.Linq.XName name);
new System.Xml.Linq.XElement : System.Xml.Linq.XName -> System.Xml.Linq.XElement
Public Sub New (name As XName)

Parameters

name
XName

An XName that contains the name of the element.

Examples

The following example creates an element with no content.

XElement el = new XElement("Root");
Console.WriteLine(el);

Dim el As XElement = <Root/>
Console.WriteLine(el)

This example produces the following output:

<Root />

The following example creates an element in a namespace with no content. For more information, see Work with XML Namespaces.

XNamespace aw = "http://www.adventure-works.com";
XElement root = new XElement(aw + "Root");
Console.WriteLine(root);

Imports <xmlns="http://www.adventure-works.com">

Module Module1
    Sub Main()
        Dim root = <Root/>
        Console.WriteLine(root)
    End Sub
End Module

This example produces the following output:

<Root xmlns="http://www.adventure-works.com" />

Remarks

This constructor creates an element with no content and no attributes.

There is an implicit conversion from string to XName. Typical use of this constructor is to specify a string as the parameter instead of creating a new XName. When creating an element in a namespace, typical use is to use the addition operator overload with an XNamespace and a string to create an XName. For more information, see Work with XML Namespaces.

See also

Applies to

XElement(XStreamingElement)

Source:
XElement.cs
Source:
XElement.cs
Source:
XElement.cs

Initializes a new instance of the XElement class from an XStreamingElement object.

public:
 XElement(System::Xml::Linq::XStreamingElement ^ other);
public XElement (System.Xml.Linq.XStreamingElement other);
new System.Xml.Linq.XElement : System.Xml.Linq.XStreamingElement -> System.Xml.Linq.XElement
Public Sub New (other As XStreamingElement)

Parameters

other
XStreamingElement

An XStreamingElement that contains unevaluated queries that will be iterated for the contents of this XElement.

Examples

The following example creates a source XML tree, and then creates an XStreamingElement from a query on the source XML tree. It then serializes the XStreamingElement to the console, adds a new element to the source XML tree, and then serializes the XStreamingElement again. You can see that element newly added to the source XML tree is not included in the first serialization, but is included in the second.

XElement src = new XElement("Root",
                   new XElement("Child1", 1),
                   new XElement("Child2", 2),
                   new XElement("Child3", 3)
               );
XStreamingElement xse = new XStreamingElement("NewRoot",
                            from el in src.Elements()
                            where (int)el >= 2
                            select el
                        );
Console.WriteLine(xse);
src.Add(new XElement("Child4", 4));
Console.WriteLine("----");
Console.WriteLine(xse);

Dim src As XElement = _
        <Root>
            <Child1>1</Child1>
            <Child2>2</Child2>
            <Child3>3</Child3>
        </Root>
Dim xse As XStreamingElement = New XStreamingElement("NewRoot", _
        From el In src.Elements() _
        Where (CInt(el) >= 2) _
        Select el _
)
Console.WriteLine(xse)
src.Add(New XElement("Child4", 4))
Console.WriteLine("----")
Console.WriteLine(xse)

This example produces the following output:

<NewRoot>
  <Child2>2</Child2>
  <Child3>3</Child3>
</NewRoot>
----
<NewRoot>
  <Child2>2</Child2>
  <Child3>3</Child3>
  <Child4>4</Child4>
</NewRoot>

Remarks

This constructor iterates through the contents of the specified XStreamingElement, and creates an element with its contents.

See also

Applies to

XElement(XName, Object)

Source:
XElement.cs
Source:
XElement.cs
Source:
XElement.cs

Initializes a new instance of the XElement class with the specified name and content.

public:
 XElement(System::Xml::Linq::XName ^ name, System::Object ^ content);
public XElement (System.Xml.Linq.XName name, object content);
public XElement (System.Xml.Linq.XName name, object? content);
new System.Xml.Linq.XElement : System.Xml.Linq.XName * obj -> System.Xml.Linq.XElement
Public Sub New (name As XName, content As Object)

Parameters

name
XName

An XName that contains the element name.

content
Object

The contents of the element.

Examples

The following example creates an XML tree. The content of the new element comes from a LINQ query.

XElement xmlTree1 = new XElement("Root",
    new XElement("Child1", 1),
    new XElement("Child2", 2),
    new XElement("Child3", 3),
    new XElement("Child4", 4),
    new XElement("Child5", 5),
    new XElement("Child6", 6)
);

XElement xmlTree2 = new XElement("Root",
    from el in xmlTree1.Elements()
    where((int)el >= 3 && (int)el <= 5)
    select el
);
Console.WriteLine(xmlTree2);

Dim xmlTree1 As XElement = _
        <Root>
            <Child1>1</Child1>
            <Child2>2</Child2>
            <Child3>3</Child3>
            <Child4>4</Child4>
            <Child5>5</Child5>
            <Child6>6</Child6>
        </Root>

Dim xmlTree2 As XElement = _
    <Root>
        <%= From el In xmlTree1.Elements() _
            Where el.Value >= 3 And el.Value <= 5 _
            Select el %>
    </Root>

Console.WriteLine(xmlTree2)

This example produces the following output:

<Root>
  <Child3>3</Child3>
  <Child4>4</Child4>
  <Child5>5</Child5>
</Root>

The following example creates an XML tree with a variety of types of content.

XElement root;

// String content:
root = new XElement("Root", "Some text");
Console.WriteLine(root);

// XElement object content:
root = new XElement("Root",
    new XElement("NewChild", "n")
);
Console.WriteLine(root);

// XAttribute object content:
root = new XElement("Root",
    new XAttribute("NewAttribute", "n")
);
Console.WriteLine(root);

// Double content:
double dbl = 12.345;
root = new XElement("Root", dbl);
Console.WriteLine(root);

// DateTime content:
DateTime dt = new DateTime(2006, 10, 6, 12, 30, 00);
root = new XElement("Root", dt);
Console.WriteLine(root);

// String array content:
// Any collection other than a collection of XElement or XAttribute objects
// are converted to strings. The strings are concatenated and added.
string[] stringArray = {
    "abc",
    "def",
    "ghi"
};
root = new XElement("Root", stringArray);
Console.WriteLine(root);

// XElement object array content:
XElement[] ellArray = {
    new XElement("NewChild1", 1),
    new XElement("NewChild2", 2),
    new XElement("NewChild3", 3)
};
root = new XElement("Root", ellArray);
Console.WriteLine(root);

// XAttribute object array content:
XAttribute[] attArray = {
    new XAttribute("NewAtt1", 1),
    new XAttribute("NewAtt2", 2),
    new XAttribute("NewAtt3", 3)
};
root = new XElement("Root", attArray);
Console.WriteLine(root);

Dim root As XElement

' String content:
root = <Root>Some text</Root>
Console.WriteLine(root)

' XElement object content:
root = <Root>
           <NewChild>n</NewChild>
       </Root>
Console.WriteLine(root)

' XAttribute object content:
root = <Root NewAttribute="n"/>
Console.WriteLine(root)

' Double content:
Dim dbl As Double = 12.345
root = <Root><%= dbl %></Root>
Console.WriteLine(root)

' DateTime content:
Dim dt As DateTime = New DateTime(2006, 10, 6, 12, 30, 0)
root = <Root><%= dt %></Root>
Console.WriteLine(root)

' String array content:
' Any collection other than a collection of XElement or XAttribute objects
' are converted to strings. The strings are concatenated and added.

Dim stringArray As String() = { _
    "abc", _
    "def", _
    "ghi" _
}
root = <Root><%= stringArray %></Root>
Console.WriteLine(root)

' XElement object array content:
Dim ellArray As XElement() = { _
    <NewChild1>1</NewChild1>, _
    <NewChild2>2</NewChild2>, _
    <NewChild3>3</NewChild3> _
}

root = <Root><%= ellArray %></Root>
Console.WriteLine(root)

' XAttribute object array content
Dim attArray As XAttribute() = { _
    New XAttribute("NewAtt1", 1), _
    New XAttribute("NewAtt2", 2), _
    New XAttribute("NewAtt3", 3) _
}
root = <Root><%= attArray %></Root>
Console.WriteLine(root)

This example produces the following output:

<Root>Some text</Root>
<Root>
  <NewChild>n</NewChild>
</Root>
<Root NewAttribute="n" />
<Root>12.345</Root>
<Root>2006-10-06T12:30:00</Root>
<Root>abcdefghi</Root>
<Root>
  <NewChild1>1</NewChild1>
  <NewChild2>2</NewChild2>
  <NewChild3>3</NewChild3>
</Root>
<Root NewAtt1="1" NewAtt2="2" NewAtt3="3" />

The following example creates an XML tree in a namespace.

// Create an XML tree in a namespace.
XNamespace aw = "http://www.adventure-works.com";
XElement root = new XElement(aw + "Root",
    new XElement(aw + "Child", "child content")
);
Console.WriteLine(root);

' Create an XML tree in a namespace.
Dim root As XElement = _
    <Root xmlns='http://www.adventure-works.com'>
        <Child>child content</Child>
    </Root>
Console.WriteLine(root)

This example produces the following output:

<Root xmlns="http://www.adventure-works.com">
  <Child>child content</Child>
</Root>

The following example creates an XML tree with nested namespaces.

// Create an XML tree with nested namespaces.
XNamespace aw = "http://www.adventure-works.com";
XNamespace fc = "www.fourthcoffee.com";
XDocument root = new XDocument(
    new XDeclaration("1.0", "utf-8", "yes"),
    new XElement(aw + "Root",
        new XElement(fc + "Child",
            new XElement(aw + "DifferentChild", "other content")
        )
    )
);
Console.WriteLine(root);

' Create an XML tree with nested namespaces.
Dim root As XDocument = _
    <?xml version='1.0'?>
    <Root xmlns='http://www.adventure-works.com'>
        <Child xmlns='www.fourthcoffee.com'>
        <DifferentChild xmlns='http://www.adventure-works.com'>other content</DifferentChild>
        </Child>
    </Root>
Console.WriteLine(root)

This example produces the following output:

<Root xmlns="http://www.adventure-works.com">
  <Child xmlns="www.fourthcoffee.com">
    <DifferentChild xmlns="http://www.adventure-works.com">other content</DifferentChild>
  </Child>
</Root>

Remarks

This constructor creates an element with the specified content and attributes.

There is an implicit conversion from string to XName. Typical use of this constructor is to specify a string as the parameter instead of creating a new XName.

When creating an element in a namespace, typical use is to use the addition operator overload with an XNamespace and a string to create an XName. For more information, see Work with XML Namespaces.

For details about the valid content that can be passed to this constructor, see Valid Content of XElement and XDocument Objects.

See also

Applies to

XElement(XName, Object[])

Source:
XElement.cs
Source:
XElement.cs
Source:
XElement.cs

Initializes a new instance of the XElement class with the specified name and content.

public:
 XElement(System::Xml::Linq::XName ^ name, ... cli::array <System::Object ^> ^ content);
public XElement (System.Xml.Linq.XName name, params object[] content);
public XElement (System.Xml.Linq.XName name, params object?[] content);
new System.Xml.Linq.XElement : System.Xml.Linq.XName * obj[] -> System.Xml.Linq.XElement
Public Sub New (name As XName, ParamArray content As Object())

Parameters

name
XName

An XName that contains the element name.

content
Object[]

The initial content of the element.

Examples

The following example creates an XML tree. The content of the new element comes from a LINQ query.

XElement xmlTree1 = new XElement("Root",
    new XElement("Child1", 1),
    new XElement("Child2", 2),
    new XElement("Child3", 3),
    new XElement("Child4", 4),
    new XElement("Child5", 5),
    new XElement("Child6", 6)
);

XElement xmlTree2 = new XElement("Root",
    from el in xmlTree1.Elements()
    where((int)el >= 3 && (int)el <= 5)
    select el
);
Console.WriteLine(xmlTree2);

Dim xmlTree1 As XElement = _
        <Root>
            <Child1>1</Child1>
            <Child2>2</Child2>
            <Child3>3</Child3>
            <Child4>4</Child4>
            <Child5>5</Child5>
            <Child6>6</Child6>
        </Root>

Dim xmlTree2 As XElement = _
    <Root>
        <%= From el In xmlTree1.Elements() _
            Where el.Value >= 3 And el.Value <= 5 _
            Select el %>
    </Root>

Console.WriteLine(xmlTree2)

This example produces the following output:

<Root>
  <Child3>3</Child3>
  <Child4>4</Child4>
  <Child5>5</Child5>
</Root>

The following example creates an XML tree with a variety of types of content.

XElement root;

// String content:
root = new XElement("Root", "Some text");
Console.WriteLine(root);

// XElement object content:
root = new XElement("Root",
    new XElement("NewChild", "n")
);
Console.WriteLine(root);

// XAttribute object content:
root = new XElement("Root",
    new XAttribute("NewAttribute", "n")
);
Console.WriteLine(root);

// Double content:
double dbl = 12.345;
root = new XElement("Root", dbl);
Console.WriteLine(root);

// DateTime content:
DateTime dt = new DateTime(2006, 10, 6, 12, 30, 00);
root = new XElement("Root", dt);
Console.WriteLine(root);

// String array content:
// Any collection other than a collection of XElement or XAttribute objects
// are converted to strings. The strings are concatenated and added.
string[] stringArray = {
    "abc",
    "def",
    "ghi"
};
root = new XElement("Root", stringArray);
Console.WriteLine(root);

// XElement object array content:
XElement[] ellArray = {
    new XElement("NewChild1", 1),
    new XElement("NewChild2", 2),
    new XElement("NewChild3", 3)
};
root = new XElement("Root", ellArray);
Console.WriteLine(root);

// XAttribute object array content:
XAttribute[] attArray = {
    new XAttribute("NewAtt1", 1),
    new XAttribute("NewAtt2", 2),
    new XAttribute("NewAtt3", 3)
};
root = new XElement("Root", attArray);
Console.WriteLine(root);

Dim root As XElement

' String content:
root = <Root>Some text</Root>
Console.WriteLine(root)

' XElement object content:
root = <Root>
           <NewChild>n</NewChild>
       </Root>
Console.WriteLine(root)

' XAttribute object content:
root = <Root NewAttribute="n"/>
Console.WriteLine(root)

' Double content:
Dim dbl As Double = 12.345
root = <Root><%= dbl %></Root>
Console.WriteLine(root)

' DateTime content:
Dim dt As DateTime = New DateTime(2006, 10, 6, 12, 30, 0)
root = <Root><%= dt %></Root>
Console.WriteLine(root)

' String array content:
' Any collection other than a collection of XElement or XAttribute objects
' are converted to strings. The strings are concatenated and added.

Dim stringArray As String() = { _
    "abc", _
    "def", _
    "ghi" _
}
root = <Root><%= stringArray %></Root>
Console.WriteLine(root)

' XElement object array content:
Dim ellArray As XElement() = { _
    <NewChild1>1</NewChild1>, _
    <NewChild2>2</NewChild2>, _
    <NewChild3>3</NewChild3> _
}

root = <Root><%= ellArray %></Root>
Console.WriteLine(root)

' XAttribute object array content
Dim attArray As XAttribute() = { _
    New XAttribute("NewAtt1", 1), _
    New XAttribute("NewAtt2", 2), _
    New XAttribute("NewAtt3", 3) _
}
root = <Root><%= attArray %></Root>
Console.WriteLine(root)

This example produces the following output:

<Root>Some text</Root>
<Root>
  <NewChild>n</NewChild>
</Root>
<Root NewAttribute="n" />
<Root>12.345</Root>
<Root>2006-10-06T12:30:00</Root>
<Root>abcdefghi</Root>
<Root>
  <NewChild1>1</NewChild1>
  <NewChild2>2</NewChild2>
  <NewChild3>3</NewChild3>
</Root>
<Root NewAtt1="1" NewAtt2="2" NewAtt3="3" />

The following example creates an XML tree in a namespace.

// Create an XML tree in a namespace.
XNamespace aw = "http://www.adventure-works.com";
XElement root = new XElement(aw + "Root",
    new XElement(aw + "Child", "child content")
);
Console.WriteLine(root);

' Create an XML tree in a namespace.
Dim root As XElement = _
    <Root xmlns='http://www.adventure-works.com'>
        <Child>child content</Child>
    </Root>
Console.WriteLine(root)

This example produces the following output:

<Root xmlns="http://www.adventure-works.com">
  <Child>child content</Child>
</Root>

The following example creates an XML tree with nested namespaces.

// Create an XML tree with nested namespaces.
XNamespace aw = "http://www.adventure-works.com";
XNamespace fc = "www.fourthcoffee.com";
XElement root = new XElement(aw + "Root",
    new XElement(fc + "Child",
        new XElement(aw + "DifferentChild", "other content")
    )
);
Console.WriteLine(root);

' Create an XML tree with nested namespaces.
Dim root As XDocument = _
    <?xml version='1.0'?>
    <Root xmlns='http://www.adventure-works.com'>
        <Child xmlns='www.fourthcoffee.com'>
        <DifferentChild xmlns='http://www.adventure-works.com'>other content</DifferentChild>
        </Child>
    </Root>
Console.WriteLine(root)

This example produces the following output:

<Root xmlns="http://www.adventure-works.com">
  <Child xmlns="www.fourthcoffee.com">
    <DifferentChild xmlns="http://www.adventure-works.com">other content</DifferentChild>
  </Child>
</Root>

Remarks

This constructor creates an element with the specified content and attributes.

There is an implicit conversion from string to XName. Typical use of this constructor is to specify a string as the parameter instead of creating a new XName.

When creating an element in a namespace, typical use is to use the addition operator overload with an XNamespace and a string to create an XName. For more information, see Work with XML Namespaces.

For details about the valid content that can be passed to this constructor, see Valid Content of XElement and XDocument Objects.

See also

Applies to