XslCompiledTransform.Transform Method (IXPathNavigable, XmlWriter)

Note: This method is new in the .NET Framework version 2.0.

Executes the transform using the input document specified by the IXPathNavigable object and outputs the results to an XmlWriter.

Namespace: System.Xml.Xsl
Assembly: System.Xml (in system.xml.dll)

public void Transform (
	IXPathNavigable input,
	XmlWriter results
public void Transform (
	IXPathNavigable input, 
	XmlWriter results
public function Transform (
	input : IXPathNavigable, 
	results : XmlWriter



An object implementing the IXPathNavigable interface. In the Microsoft .NET Framework, this can be either an XmlNode (typically an XmlDocument), or an XPathDocument containing the data to be transformed.


The XmlWriter to which you want to output.

If the style sheet contains an xsl:output element, you should create the XmlWriter using the XmlWriterSettings object returned from the OutputSettings property. This ensures that the XmlWriter has the correct output settings.

Exception typeCondition


The input or results value is a null reference (Nothing in Visual Basic).


There was an error executing the XSLT transform.

If the XSLT document() function is enabled, it is resolved using an XmlUrlResolver with no user credentials. If the external resource is located on a network resource that requires authentication, use the overload that takes an XmlResolver as one of its arguments and specify an XmlResolver with the necessary credentials.

This method does not support the xsl:strip-space element. If your compiled style sheet included the xsl:strip-space element, you must use the Transform overload which takes an XmlReader as the input argument.

The IXPathNavigable interface is implemented in the XmlNode and XPathDocument classes. These classes represent an in-memory cache of XML data.

  • The XmlNode class is based on the W3C Document Object Model (DOM) and includes editing capabilities.

  • The XPathDocument class is a read-only data store based on the XPath data model. XPathDocument is the recommended class for XSLT processing. It provides faster performance when compared to the XmlNode class.

Transformations apply to the document as a whole. In other words, if you pass in a node other than the document root node, this does not prevent the transformation process from accessing all nodes in the loaded document. To transform a node fragment, you must create an object containing just the node fragment, and pass that object to the Transform method. For more information, see How to: Transform a Node Fragment.

The following example executes an XSLT transformation and outputs to an XmlWriter object.

// Load the style sheet.
XslCompiledTransform xslt = new XslCompiledTransform();

// Create the writer.
XmlWriterSettings settings = new XmlWriterSettings();
settings.Indent = true;
settings.IndentChars = "\t";
XmlWriter writer = XmlWriter.Create("output.xml", settings);

// Execute the transformation.
xslt.Transform(new XPathDocument("books.xml"), writer);

Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0

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