SignedXml.XmlDsigXsltTransformUrl Field

Definition

Namespace:

System.Security.Cryptography.Xml

Assembly:

System.Security.Cryptography.Xml.dll

Source:

SignedXml.cs

Represents the Uniform Resource Identifier (URI) for XSLT transformations. This field is constant.

C#

public const string XmlDsigXsltTransformUrl;

Field Value

String

Examples

The following code example demonstrates how to use members of the XmlDsigXsltTransform class.

C#

using System;
using System.IO;
using System.Xml;
using System.Security.Cryptography;
using System.Security.Cryptography.Xml;
using System.Text;

class Class1
{
    [STAThread]
    static void Main(string[] args)
    {
        XmlDocument productsXml = LoadProducts();
        XmlNodeList xsltNodeList = GetXsltAsNodeList();
        TransformDoc(productsXml, xsltNodeList);

        // Use XmlDsigXsltTransform to resolve a Uri.
        Uri baseUri = new Uri("http://www.contoso.com");
        string relativeUri = "xml";
        Uri absoluteUri = ResolveUris(baseUri, relativeUri);

        Console.WriteLine("This sample completed successfully; " +
            "press Enter to exit.");
        Console.ReadLine();
    }

    private static void TransformDoc(
        XmlDocument xmlDoc, 
        XmlNodeList xsltNodeList)
    {
        try 
        {
            // Construct a new XmlDsigXsltTransform.
            XmlDsigXsltTransform xmlTransform = 
                new XmlDsigXsltTransform();

            // Load the Xslt tranform as a node list.
            xmlTransform.LoadInnerXml(xsltNodeList);

            // Load the Xml document to perform the tranform on.
            XmlNamespaceManager namespaceManager;
            namespaceManager = new XmlNamespaceManager(xmlDoc.NameTable);

            XmlNodeList productsNodeList;
            productsNodeList = xmlDoc.SelectNodes("//.", namespaceManager);

            xmlTransform.LoadInput(productsNodeList);

            // Retrieve the output from the transform.
            Stream outputStream = (Stream)
                xmlTransform.GetOutput(typeof(System.IO.Stream));

            // Read the output stream into a stream reader.
            StreamReader streamReader =
                new StreamReader(outputStream);

            // Read the stream into a string.
            string outputMessage = streamReader.ReadToEnd();

            // Close the streams.
            outputStream.Close();
            streamReader.Close();

            // Display to the console the Xml before and after
            // encryption.
            Console.WriteLine("\nResult of transformation: " + outputMessage);
            ShowTransformProperties(xmlTransform);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Caught exception in TransformDoc method: " + 
                ex.ToString());
        }
    }
    
    private static XmlNodeList GetXsltAsNodeList()
    {
        string transformXml = "<xsl:transform version='1.0' ";
        transformXml += "xmlns:xsl='http://www.w3.org/1999/XSL/Transform'>";
        transformXml += "<xsl:template match='products'>";
        transformXml += "<table><tr><td>ProductId</td><td>Name</td></tr>";
        transformXml += "<xsl:apply-templates/></table></xsl:template>";
        transformXml += "<xsl:template match='product'><tr>";
        transformXml += "<xsl:apply-templates/></tr></xsl:template>";
        transformXml += "<xsl:template match='productid'><td>";
        transformXml += "<xsl:apply-templates/></td></xsl:template>";
        transformXml += "<xsl:template match='description'><td>";
        transformXml += "<xsl:apply-templates/></td></xsl:template>";
        transformXml += "</xsl:transform>";

        Console.WriteLine("\nCreated the following Xslt tranform:");
        Console.WriteLine(transformXml);

        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.LoadXml(transformXml);
        return xmlDoc.GetElementsByTagName("xsl:transform");
    }

    // Encrypt the text in the specified XmlDocument.
    private static void ShowTransformProperties(
        XmlDsigXsltTransform xmlTransform)
    {
        string classDescription = xmlTransform.ToString();
        Console.WriteLine("\n** Summary for " + classDescription + " **");

        // Retrieve the XML representation of the current transform.
        XmlElement xmlInTransform = xmlTransform.GetXml();
        Console.WriteLine("Xml representation of the current transform:\n" +
            xmlInTransform.OuterXml);

        // Ensure the transform is using the proper algorithm.
        xmlTransform.Algorithm =
            SignedXml.XmlDsigXsltTransformUrl;
        Console.WriteLine("Algorithm used: " + classDescription);

        // Retrieve the valid input types for the current transform.
        Type[] validInTypes = xmlTransform.InputTypes;
        Console.WriteLine("Transform accepts the following inputs:");
        for (int i=0; i<validInTypes.Length; i++)
        {
            Console.WriteLine("\t" + validInTypes[i].ToString());
        }

        Type[] validOutTypes = xmlTransform.OutputTypes;
        Console.WriteLine("Transform outputs in the following types:");
        for (int i=validOutTypes.Length-1; i >= 0; i--)
        {
            Console.WriteLine("\t " + validOutTypes[i].ToString());

            if (validOutTypes[i] == typeof(object))
            {
                object outputObject = xmlTransform.GetOutput();
            }
        }
    }

    // Create an XML document describing various products.
    private static XmlDocument LoadProducts()
    {
        string contosoProducts = "<?xml version='1.0'?>";
        contosoProducts += "<products>";
        contosoProducts += "<product><productid>1</productid>";
        contosoProducts += "<description>Widgets</description></product>";
        contosoProducts += "<product><productid>2</productid>";
        contosoProducts += "<description>Gadgits</description></product>";
        contosoProducts += "</products>";

        Console.WriteLine(
            "\nCreated the following Xml document for tranformation:");
        Console.WriteLine(contosoProducts);

        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.LoadXml(contosoProducts);
        return xmlDoc;
    }

    // Resolve the specified base and relative Uri's .
    private static Uri ResolveUris(Uri baseUri, string relativeUri)
    {
        XmlUrlResolver xmlResolver = new XmlUrlResolver();
        xmlResolver.Credentials = 
            System.Net.CredentialCache.DefaultCredentials;

        XmlDsigXsltTransform xmlTransform =
            new XmlDsigXsltTransform();
        xmlTransform.Resolver = xmlResolver;

        Uri absoluteUri = xmlResolver.ResolveUri(baseUri, relativeUri);
        if (absoluteUri != null)
        {
            Console.WriteLine(
                "\nResolved the base Uri and relative Uri to the following:");
            Console.WriteLine(absoluteUri.ToString());
        }
        else
        {
            Console.WriteLine(
                "Unable to resolve the base Uri and relative Uri");
        }
        return absoluteUri;
    }
}
//
// This sample produces the following output:
//
// Created the following Xml document for tranformation:
// <?xml version='1.0'?><products><product><productid>1</productid><descriptio
// n>Widgets</description></product><product><productid>2</productid><descript
// ion>Gadgits</description></product></products>
// 
// Created the following Xslt tranform:
// <xsl:transform version='1.0' xmlns:xsl='http://www.w3.org/1999/XSL/Transfor
// m'><xsl:template match='products'><table><tr><td>ProductId</td><td>Name</td
// ></tr><xsl:apply-templates/></table></xsl:template><xsl:template match='pro
// duct'><tr><xsl:apply-templates/></tr></xsl:template><xsl:emplate match='pro
// ductid'><td><xsl:apply-templates/></td></xsl:template><xsl:template match='
// description'><td><xsl:apply-templates/></td></xsl:template></xsl:transform>
// 
// Result of transformation: <table><tr><td>ProductId</td><td>Name</td></tr><t
// r><td>1</td><td>Widgets</td></tr><tr><td>2</td><td>Gadgits</td></tr></table
// >
//
// ** Summary for System.Security.Cryptography.Xml.XmlDsigXsltTransform **
// Xml representation of the current transform:
// <Transform Algorithm="http://www.w3.org/TR/1999/REC-xslt-19991116" xmlns="h
// ttp://www.w3.org/2000/09/xmldsig#"><xsl:transform version="1.0" xmlns:xsl="
// http://www.w3.org/1999/XSL/Transform"><xsl:template match="products"><table
//  xmlns=""><tr><td>ProductId</td><td>Name</td></tr><xsl:apply-templates /></
// table></xsl:template><xsl:template match="product"><tr xmlns=""><xsl:apply-
// templates /></tr></xsl:template><xsl:template match="productid"><td xmlns="
// "><xsl:apply-templates /></td></xsl:template><xsl:template match="descripti
// on"><td xmlns=""><xsl:apply-templates /></td></xsl:template></xsl:transform
// ></Transform>
// Algorithm used: System.Security.Cryptography.Xml.XmlDsigXsltTransform
// Transform accepts the following inputs:
// System.IO.Stream
// System.Xml.XmlDocument
// System.Xml.XmlNodeList
// Transform outputs in the following types:
// System.IO.Stream
// 
// Resolved the base Uri and relative Uri to the following:
// http://www.contoso.com/xml
// This sample completed successfully; press Enter to exit.

Remarks

The value of the XmlDsigXsltTransformUrl field is http://www.w3.org/TR/1999/REC-xslt-19991116.

Use this field to conveniently supply a value to one of the URI attributes of an element used for XMLDSIG.

The XmlDsigXsltTransform class implements the transform described by the XmlDsigXsltTransformUrl field.

For more information, see the World Wide Web Consortium (W3C) specification.

Applies to