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XmlTextReader Constructor (String, XmlNodeType, XmlParserContext)

.NET Framework 3.5

Other Versions

Initializes a new instance of the XmlTextReader class with the specified string, XmlNodeType, and XmlParserContext.

Namespace: System.Xml
Assembly: System.Xml (in System.Xml.dll)

Syntax

C++

JScript

public XmlTextReader(
	string xmlFragment,
	XmlNodeType fragType,
	XmlParserContext context
)

Parameters

xmlFragment: Type: System.String
The string containing the XML fragment to parse.

fragType: Type: System.Xml.XmlNodeType
The XmlNodeType of the XML fragment. This also determines what the fragment string can contain. (See table below.)

context: Type: System.Xml.XmlParserContext
The XmlParserContext in which the xmlFragment is to be parsed. This includes the XmlNameTable to use, encoding, namespace scope, the current xml:lang, and the xml:space scope.

Exceptions

Exception	Condition
XmlException	fragType is not an Element, Attribute, or Document XmlNodeType.
ArgumentNullException	xmlFragment is null.

Remarks

Note:
In the .NET Framework version 2.0 release, the recommended practice is to create XmlReader instances using the XmlReader.Create method. This allows you to take full advantage of the new features introduced in this release. For more information, see Creating XML Readers.

This constructor parses the given string as a fragment of XML. If the XML fragment is an element or attribute, you can bypass the root level rules for well-formed XML documents. This constructor can handle strings returned from ReadInnerXml.

The following table lists valid values for fragType and how the reader parses each of the different node types.

XmlNodeType	Fragment May Contain
Element	Any valid element content (for example, any combination of elements, comments, processing instructions, CDATA sections, text, and entity references). An XML declaration can also be supplied. This allows you to specify the encoding for the XML fragment, rather than having to set it on the XmlParserContext object.
Attribute	The value of an attribute (the part inside the quotes).
Document	The contents of an entire XML document. This enforces document level rules.

XmlNodeType

Fragment May Contain

Element

Any valid element content (for example, any combination of elements, comments, processing instructions, CDATA sections, text, and entity references).

An XML declaration can also be supplied. This allows you to specify the encoding for the XML fragment, rather than having to set it on the XmlParserContext object.

Attribute

The value of an attribute (the part inside the quotes).

Document

The contents of an entire XML document. This enforces document level rules.

Examples

The following example parses an XML fragment. It uses the XmlParserContext and its XmlNamespaceManager to handle namespace resolution.

C++

using System;
using System.IO;
using System.Xml;

public class Sample 
{
  public static void Main()
  {

    //Create the XML fragment to be parsed.
    string xmlFrag ="<book> " +
                    "<title>Pride And Prejudice</title>" +
                    "<bk:genre>novel</bk:genre>" +
                    "</book>"; 

    //Create the XmlNamespaceManager.
    NameTable nt = new NameTable();
    XmlNamespaceManager nsmgr = new XmlNamespaceManager(nt);
    nsmgr.AddNamespace("bk", "urn:sample");

    //Create the XmlParserContext.
    XmlParserContext context = new XmlParserContext(null, nsmgr, null, XmlSpace.None);

    //Create the reader. 
    XmlTextReader reader = new XmlTextReader(xmlFrag, XmlNodeType.Element, context);

    //Parse the XML.  If they exist, display the prefix and   
    //namespace URI of each element. 
    while (reader.Read()){
      if (reader.IsStartElement()){
        if (reader.Prefix==String.Empty)
           Console.WriteLine("<{0}>", reader.LocalName);
        else{
            Console.Write("<{0}:{1}>", reader.Prefix, reader.LocalName);
            Console.WriteLine(" The namespace URI is " + reader.NamespaceURI);
        }
      }
    }

    //Close the reader.
    reader.Close();     

  }
} // End class

CPP_OLD

#using <mscorlib.dll>
#using <System.Xml.dll>
using namespace System;
using namespace System::IO;
using namespace System::Xml;

int main() 
{
   // Create the XML fragment to be parsed.
   String* xmlFrag =S"<book> <title>Pride And Prejudice</title> <bk:genre>novel</bk:genre> </book>";

   // Create the XmlNamespaceManager.
   NameTable* nt = new NameTable();
   XmlNamespaceManager* nsmgr = new XmlNamespaceManager(nt);
   nsmgr -> AddNamespace(S"bk", S"urn:sample");

   // Create the XmlParserContext.
   XmlParserContext* context = new XmlParserContext(0, nsmgr, 0, XmlSpace::None);

   // Create the reader. 
   XmlTextReader* reader = new XmlTextReader(xmlFrag, XmlNodeType::Element, context);

   // Parse the XML.  If they exist, display the prefix and  
   // namespace URI of each element.
   while (reader -> Read()) 
   {
      if (reader -> IsStartElement()) 
      {
         if (reader -> Prefix == String::Empty)
            Console::WriteLine(S"< {0}>", reader -> LocalName);
         else 
         {
            Console::Write(S"< {0}: {1}>", reader -> Prefix, reader -> LocalName);
            Console::WriteLine(S" The namespace URI is {0}", reader -> NamespaceURI);
         }
      }
   }

   // Close the reader.
   reader -> Close();
}

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information