AsnEncodedData Class

 

Represents Abstract Syntax Notation One (ASN.1)-encoded data.

Namespace:   System.Security.Cryptography
Assembly:  System (in System.dll)


public class AsnEncodedData

NameDescription
System_CAPS_protmethodAsnEncodedData()

Initializes a new instance of the AsnEncodedData class.

System_CAPS_pubmethodAsnEncodedData(AsnEncodedData)

Initializes a new instance of the AsnEncodedData class using an instance of the AsnEncodedData class.

System_CAPS_pubmethodAsnEncodedData(Byte[])

Initializes a new instance of the AsnEncodedData class using a byte array.

System_CAPS_pubmethodAsnEncodedData(Oid, Byte[])

Initializes a new instance of the AsnEncodedData class using an Oid object and a byte array.

System_CAPS_pubmethodAsnEncodedData(String, Byte[])

Initializes a new instance of the AsnEncodedData class using a byte array.

NameDescription
System_CAPS_pubpropertyOid

Gets or sets the Oid value for an AsnEncodedData object.

System_CAPS_pubpropertyRawData

Gets or sets the Abstract Syntax Notation One (ASN.1)-encoded data represented in a byte array.

NameDescription
System_CAPS_pubmethodCopyFrom(AsnEncodedData)

Copies information from an AsnEncodedData object.

System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethodFinalize()

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodFormat(Boolean)

Returns a formatted version of the Abstract Syntax Notation One (ASN.1)-encoded data as a string.

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_protmethodMemberwiseClone()

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

Abstract Syntax Notation One (ASN.1), which is defined in CCITT Recommendation X.208, is a way to specify abstract objects that will be serially transmitted. The set of ASN.1 rules for representing such objects as strings of ones and zeros is called the Distinguished Encoding Rules (DER), and is defined in CCITT Recommendation X.509, Section 8.7. These encoding methods are currently used by the cryptography namespace in the .NET Framework.

Note that if an unknown data type is encountered while accessing an instance of this class, data is returned as a hexadecimal string.

The following code example shows how to use the AsnEncodedData class.

using System;
using System.Security.Cryptography;
using System.Security.Cryptography.X509Certificates;

class AsnEncodedDataSample
{
	static void Main()
	{		
		//The following example demonstrates the usage the AsnEncodedData classes.
		// Asn encoded data is read from the extensions of an X509 certificate.
		try
		{
			// Open the certificate store.
			X509Store store = new X509Store("MY", StoreLocation.CurrentUser);
			store.Open(OpenFlags.ReadOnly | OpenFlags.OpenExistingOnly);
			X509Certificate2Collection collection = (X509Certificate2Collection)store.Certificates;
			X509Certificate2Collection fcollection = (X509Certificate2Collection)collection.Find(X509FindType.FindByTimeValid, DateTime.Now, false);
			// Select one or more certificates to display extensions information.
			X509Certificate2Collection scollection = X509Certificate2UI.SelectFromCollection(fcollection, "Certificate Select", "Select certificates from the following list to get extension information on that certificate", X509SelectionFlag.MultiSelection);

			// Create a new AsnEncodedDataCollection object.
			AsnEncodedDataCollection asncoll = new AsnEncodedDataCollection();
			for (int i = 0; i < scollection.Count; i++)
			{
				// Display certificate information.
				Console.ForegroundColor = ConsoleColor.Red;
				Console.WriteLine("Certificate name: {0}", scollection[i].GetName());
				Console.ResetColor();
				// Display extensions information.
				foreach (X509Extension extension in scollection[i].Extensions)
				{
					// Create an AsnEncodedData object using the extensions information.
					AsnEncodedData asndata = new AsnEncodedData(extension.Oid, extension.RawData);
					Console.ForegroundColor = ConsoleColor.Green;
					Console.WriteLine("Extension type: {0}", extension.Oid.FriendlyName);
					Console.WriteLine("Oid value: {0}",asndata.Oid.Value);
					Console.WriteLine("Raw data length: {0} {1}", asndata.RawData.Length, Environment.NewLine);
					Console.ResetColor();
					Console.WriteLine(asndata.Format(true));
					Console.WriteLine(Environment.NewLine);
					// Add the AsnEncodedData object to the AsnEncodedDataCollection object.
					asncoll.Add(asndata);
				}
				Console.WriteLine(Environment.NewLine);
			}
			Console.ForegroundColor = ConsoleColor.Red;
			Console.WriteLine("Number of AsnEncodedData items in the collection: {0} {1}", asncoll.Count, Environment.NewLine);
			Console.ResetColor();

			store.Close();
			//Create an enumerator for moving through the collection.
			AsnEncodedDataEnumerator asne = asncoll.GetEnumerator();
			//You must execute a MoveNext() to get to the first item in the collection.
			asne.MoveNext();
			// Write out AsnEncodedData in the collection.
			Console.ForegroundColor = ConsoleColor.Blue;
			Console.WriteLine("First AsnEncodedData in the collection: {0}", asne.Current.Format(true));
			Console.ResetColor();

			asne.MoveNext();
			Console.ForegroundColor = ConsoleColor.DarkBlue;
			Console.WriteLine("Second AsnEncodedData in the collection: {0}", asne.Current.Format(true));
			Console.ResetColor();
			//Return index in the collection to the beginning.
			asne.Reset();
		}
		catch (CryptographicException)
		{
			Console.WriteLine("Information could not be written out for this certificate.");
		}
	}
}

.NET Framework
Available since 2.0

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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