XDocumentType Class
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Represents an XML Document Type Definition (DTD).
Inheritance Hierarchy
System.Object
System.Xml.Linq.XObject
System.Xml.Linq.XNode
System.Xml.Linq.XDocumentType
Namespace: System.Xml.Linq
Assembly: System.Xml.Linq (in System.Xml.Linq.dll)
Syntax
'Declaration
Public Class XDocumentType _
Inherits XNode
public class XDocumentType : XNode
The XDocumentType type exposes the following members.
Constructors
| Name | Description | |
|---|---|---|
.gif "Public method") .gif "Supported by Silverlight for Windows Phone") .gif "Supported by Xbox 360") |
XDocumentType(XDocumentType) | Initializes an instance of the XDocumentType class from another XDocumentType object. |
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XDocumentType(String, String, String, String) | Initializes an instance of the XDocumentType class. |
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Properties
| Name | Description | |
|---|---|---|
.gif "Public property") |
BaseUri | Gets the base URI for this XObject. (Inherited from XObject.) |
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Document | Gets the XDocument for this XObject. (Inherited from XObject.) |
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InternalSubset | Gets or sets the internal subset for this Document Type Definition (DTD). |
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Name | Gets or sets the name for this Document Type Definition (DTD). |
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NextNode | Gets the next sibling node of this node. (Inherited from XNode.) |
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NodeType | Gets the node type for this node. (Overrides XObject.NodeType.) |
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Parent | Gets the parent XElement of this XObject. (Inherited from XObject.) |
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PreviousNode | Gets the previous sibling node of this node. (Inherited from XNode.) |
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PublicId | Gets or sets the public identifier for this Document Type Definition (DTD). |
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SystemId | Gets or sets the system identifier for this Document Type Definition (DTD). |
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Methods
| Name | Description | |
|---|---|---|
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AddAfterSelf(Object) | Adds the specified content immediately after this node. (Inherited from XNode.) |
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AddAfterSelf(array<Object[]) | Adds the specified content immediately after this node. (Inherited from XNode.) |
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AddAnnotation | Adds an object to the annotation list of this XObject. (Inherited from XObject.) |
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AddBeforeSelf(Object) | Adds the specified content immediately before this node. (Inherited from XNode.) |
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AddBeforeSelf(array<Object[]) | Adds the specified content immediately before this node. (Inherited from XNode.) |
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Ancestors() | Returns a collection of the ancestor elements of this node. (Inherited from XNode.) |
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Ancestors(XName) | Returns a filtered collection of the ancestor elements of this node. Only elements that have a matching XName are included in the collection. (Inherited from XNode.) |
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Annotation(Type) | Gets the first annotation object of the specified type from this XObject. (Inherited from XObject.) |
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Annotation<T>() | Get the first annotation object of the specified type from this XObject. (Inherited from XObject.) |
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Annotations(Type) | Gets a collection of annotations of the specified type for this XObject. (Inherited from XObject.) |
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Annotations<T>() | Gets a collection of annotations of the specified type for this XObject. (Inherited from XObject.) |
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CreateReader() | Creates an XmlReader for this node. (Inherited from XNode.) |
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CreateReader(ReaderOptions) | Creates an XmlReader for this node. (Inherited from XNode.) |
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ElementsAfterSelf() | Returns a collection of the sibling elements after this node, in document order. (Inherited from XNode.) |
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ElementsAfterSelf(XName) | Returns a filtered collection of the sibling elements after this node, in document order. Only elements that have a matching XName are included in the collection. (Inherited from XNode.) |
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ElementsBeforeSelf() | Returns a collection of the sibling elements before this node, in document order. (Inherited from XNode.) |
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ElementsBeforeSelf(XName) | Returns a filtered collection of the sibling elements before this node, in document order. Only elements that have a matching XName are included in the collection. (Inherited from XNode.) |
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Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
.gif "Protected method") |
Finalize | Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.) |
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GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
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GetType | Gets the Type of the current instance. (Inherited from Object.) |
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IsAfter | Determines if the current node appears after a specified node in terms of document order. (Inherited from XNode.) |
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IsBefore | Determines if the current node appears before a specified node in terms of document order. (Inherited from XNode.) |
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MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
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NodesAfterSelf | Returns a collection of the sibling nodes after this node, in document order. (Inherited from XNode.) |
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NodesBeforeSelf | Returns a collection of the sibling nodes before this node, in document order. (Inherited from XNode.) |
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Remove | Removes this node from its parent. (Inherited from XNode.) |
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RemoveAnnotations(Type) | Removes the annotations of the specified type from this XObject. (Inherited from XObject.) |
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RemoveAnnotations<T>() | Removes the annotations of the specified type from this XObject. (Inherited from XObject.) |
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ReplaceWith(Object) | Replaces this node with the specified content. (Inherited from XNode.) |
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ReplaceWith(array<Object[]) | Replaces this node with the specified content. (Inherited from XNode.) |
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ToString() | Returns the indented XML for this node. (Inherited from XNode.) |
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ToString(SaveOptions) | Returns the XML for this node, optionally disabling formatting. (Inherited from XNode.) |
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WriteTo | Write this XDocumentType to an XmlWriter. (Overrides XNode.WriteTo(XmlWriter).) |
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Events
| Name | Description | |
|---|---|---|
.gif "Public event") |
Changed | Raised when this XObject or any of its descendants have changed. (Inherited from XObject.) |
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Changing | Raised when this XObject or any of its descendants are about to change. (Inherited from XObject.) |
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Extension Methods
| Name | Description | |
|---|---|---|
.gif "Public Extension Method") |
CreateNavigator() | Overloaded. Creates an XPathNavigator for an XNode. (Defined by Extensions.) |
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CreateNavigator(XmlNameTable) | Overloaded. Creates an XPathNavigator for an XNode. The XmlNameTable enables more efficient XPath expression processing. (Defined by Extensions.) |
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XPathEvaluate(String) | Overloaded. Evaluates an XPath expression. (Defined by Extensions.) |
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XPathEvaluate(String, IXmlNamespaceResolver) | Overloaded. Evaluates an XPath expression, resolving namespace prefixes using the specified IXmlNamespaceResolver. (Defined by Extensions.) |
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XPathSelectElement(String) | Overloaded. Selects an XElement using a XPath expression. (Defined by Extensions.) |
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XPathSelectElement(String, IXmlNamespaceResolver) | Overloaded. Selects an XElement using a XPath expression, resolving namespace prefixes using the specified IXmlNamespaceResolver. (Defined by Extensions.) |
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XPathSelectElements(String) | Overloaded. Selects a collection of elements using an XPath expression. (Defined by Extensions.) |
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XPathSelectElements(String, IXmlNamespaceResolver) | Overloaded. Selects a collection of elements using an XPath expression, resolving namespace prefixes using the specified IXmlNamespaceResolver. (Defined by Extensions.) |
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Explicit Interface Implementations
| Name | Description | |
|---|---|---|
.gif "Explicit interface implemetation") .gif "Private method") |
IXmlLineInfo.HasLineInfo | Gets a value indicating whether or not this XObject has line information. (Inherited from XObject.) |
.gif "Private property") |
IXmlLineInfo.LineNumber | Gets the line number that the underlying XmlReader reported for this XObject. (Inherited from XObject.) |
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IXmlLineInfo.LinePosition | Gets the line position that the underlying XmlReader reported for this XObject. (Inherited from XObject.) |
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Remarks
Data Type Definitions (DTD) in XML are a way to do the following:
Validate XML trees to a limited extent.
Expand entities, which is a form of text replacement.
Supply default attributes.
This class represents the XML concept of a DTD.
DTD support in LINQ to XML is limited.
LINQ to XML will expand internal entities by default, but it will not resolve external entity references unless an XmlReader with an associated XmlResolver is used to load the XML tree.
LINQ to XML will not validate a document against a DTD, but you can use a validating XmlReader to perform DTD validation if necessary.
When a document contains entity references that are defined in a DTD, the references are expanded upon creation of the XML tree. However, when you serialize or save the XML tree, the content of the expanded entities is preserved; the entity references are not.
Default attributes from the DTD will be materialized as regular attributes in the XML tree. After a default attribute from the DTD is materialized, there is no way to determine that the attribute was a default attribute from the DTD.
You can populate an XML tree with an XML document that contains an internal DTD. The XML tree will then contain a DocumentType node. When you serialize or save the tree, the internal DTD will also be saved as part of the document.
Examples
The following example shows the use of this property to retrieve the node type for an XDocumentType object.
Dim output As New StringBuilder
Dim internalSubset = _
"<!ELEMENT Pubs (Book+)>" & Environment.NewLine & _
"<!ELEMENT Book (Title, Author)>" & Environment.NewLine & _
"<!ELEMENT Title (#PCDATA)>" & Environment.NewLine & _
"<!ELEMENT Author (#PCDATA)>"
Dim doc As XDocument = _
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<!--This is a comment.-->
<?xml-stylesheet href='mystyle.css' title='Compact' type='text/css'?>
<Pubs>
<Book>
<Title>Artifacts of Roman Civilization</Title>
<Author>Moreno, Jordao</Author>
</Book>
<Book>
<Title>Midieval Tools and Implements</Title>
<Author>Gazit, Inbar</Author>
</Book>
</Pubs>
<!--This is another comment.-->
doc.FirstNode.AddAfterSelf(New XDocumentType("Pubs", Nothing, Nothing, internalSubset))
output.Append(doc.DocumentType.NodeType.ToString())
output.Append(Environment.NewLine)
OutputTextBlock.Text = output.ToString()
StringBuilder output = new StringBuilder();
string internalSubset = @"<!ELEMENT Pubs (Book+)>
<!ELEMENT Book (Title, Author)>
<!ELEMENT Title (#PCDATA)>
<!ELEMENT Author (#PCDATA)>";
string target = "xml-stylesheet";
string data = "href=\"mystyle.css\" title=\"Compact\" type=\"text/css\"";
XDocument doc = new XDocument(
new XComment("This is a comment."),
new XProcessingInstruction(target, data),
new XDocumentType("Pubs", null, null, internalSubset),
new XElement("Pubs",
new XElement("Book",
new XElement("Title", "Artifacts of Roman Civilization"),
new XElement("Author", "Moreno, Jordao")
),
new XElement("Book",
new XElement("Title", "Midieval Tools and Implements"),
new XElement("Author", "Gazit, Inbar")
)
),
new XComment("This is another comment.")
);
doc.Declaration = new XDeclaration("1.0", "utf-8", "true");
output.Append(doc.DocumentType.NodeType + Environment.NewLine);
OutputTextBlock.Text = output.ToString();
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
XNA Framework
Supported in: Xbox 360, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.
Thread Safety
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
See Also