SignedXml.AddObject(DataObject) Method

public:
 void AddObject(System::Security::Cryptography::Xml::DataObject ^ dataObject);

public void AddObject(System.Security.Cryptography.Xml.DataObject dataObject);

member this.AddObject : System.Security.Cryptography.Xml.DataObject -> unit

Public Sub AddObject (dataObject As DataObject)

Parameters

Examples

The following code example computes and XML signature.

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

public class XMLdsigsample1 
{

    static void Main(String[] args)
    {
        try
        {
            // Create example data to sign.
            XmlDocument document = new XmlDocument();
            XmlNode node = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples");
            node.InnerText = "This is some text";
            document.AppendChild(node);
            Console.WriteLine("Data to sign:\n" + document.OuterXml + "\n");
 
            // Create the SignedXml message.
            SignedXml signedXml = new SignedXml();
            RSA key = RSA.Create();
            signedXml.SigningKey = key;
 
            // Create a data object to hold the data to sign.
            DataObject dataObject = new DataObject();
            dataObject.Data = document.ChildNodes;
            dataObject.Id = "MyObjectId";

            // Add the data object to the signature.
            signedXml.AddObject(dataObject);
 
            // Create a reference to be able to package everything into the
            // message.
            Reference reference = new Reference();
            reference.Uri = "#MyObjectId";
 
            // Add the reference to the message.
            signedXml.AddReference(reference);

            // Add a KeyInfo.
            KeyInfo keyInfo = new KeyInfo();
            keyInfo.AddClause(new RSAKeyValue(key));
            signedXml.KeyInfo = keyInfo;

            // Compute the signature.
            signedXml.ComputeSignature();

            Console.WriteLine("The data was signed.");
        }
        catch(CryptographicException e)
        {
            Console.WriteLine(e.Message);
        }
    }
}

Imports System.IO
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Xml




Public Class XMLdsigsample1
   
   
   Overloads Shared Sub Main(args() As [String])
      Try
         ' Create example data to sign.
         Dim document As New XmlDocument()
         Dim node As XmlNode = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples")
         node.InnerText = "This is some text"
         document.AppendChild(node)
         Console.WriteLine(("Data to sign:" + ControlChars.Lf + document.OuterXml + ControlChars.Lf))
         
         ' Create the SignedXml message.
         Dim signedXml As New SignedXml()
         Dim key As RSA = RSA.Create()
         signedXml.SigningKey = key
         
         ' Create a data object to hold the data to sign.
         Dim dataObject As New DataObject()
         dataObject.Data = document.ChildNodes
         dataObject.Id = "MyObjectId"
         
         ' Add the data object to the signature.
         signedXml.AddObject(dataObject)
         
         ' Create a reference to be able to package everything into the
         ' message.
         Dim reference As New Reference()
         reference.Uri = "#MyObjectId"
         
         ' Add the reference to the message.
         signedXml.AddReference(reference)
         
         ' Add a KeyInfo.
         Dim keyInfo As New KeyInfo()
         keyInfo.AddClause(New RSAKeyValue(key))
         signedXml.KeyInfo = keyInfo
         
         ' Compute the signature.
         signedXml.ComputeSignature()
         
         Console.WriteLine("The data was signed.")
      Catch e As CryptographicException
         Console.WriteLine(e.Message)
      End Try
   End Sub 
End Class

Remarks

The AddObject method adds an <Object> element that represents an object to be signed to the <Signature> element of an XML digital signature.

The AddObject method internally calls the AddObject method of the Signature object encapsulated by the SignedXml object. You can also add a DataObject object by directly calling the AddObject method from the Signature property.

For more information about XML digital signatures, see the XMLDSIG specification.