AsnEncodedDataEnumerator.Current AsnEncodedDataEnumerator.Current AsnEncodedDataEnumerator.Current AsnEncodedDataEnumerator.Current Property

Definice

Získá aktuální AsnEncodedData objekt AsnEncodedDataCollection objektu.Gets the current AsnEncodedData object in an AsnEncodedDataCollection object.

public:
 property System::Security::Cryptography::AsnEncodedData ^ Current { System::Security::Cryptography::AsnEncodedData ^ get(); };
public System.Security.Cryptography.AsnEncodedData Current { get; }
member this.Current : System.Security.Cryptography.AsnEncodedData
Public ReadOnly Property Current As AsnEncodedData

Hodnota vlastnosti

Aktuální AsnEncodedData objekt v kolekci.The current AsnEncodedData object in the collection.

Příklady

Následující příklad kódu ukazuje, jak používat AsnEncodedDataEnumerator třídy.The following code example shows how to use the AsnEncodedDataEnumerator class.

#using <System.dll>
#using <System.Security.dll>

using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Security::Cryptography::X509Certificates;

int main()
{
   
   //The following example demonstrates the usage of the AsnEncodedData classes.
   // Asn encoded data is read from the extensions of an X509 certificate.
   try
   {
      
      // Open the certificate store.
      X509Store^ store = gcnew X509Store( L"MY",StoreLocation::CurrentUser );
      store->Open( static_cast<OpenFlags>(OpenFlags::ReadOnly | OpenFlags::OpenExistingOnly) );
      X509Certificate2Collection^ collection = dynamic_cast<X509Certificate2Collection^>(store->Certificates);
      X509Certificate2Collection^ fcollection = dynamic_cast<X509Certificate2Collection^>(collection->Find( X509FindType::FindByTimeValid, DateTime::Now, false ));
      
      // Select one or more certificates to display extensions information.
      X509Certificate2Collection^ scollection = X509Certificate2UI::SelectFromCollection(fcollection, L"Certificate Select",L"Select certificates from the following list to get extension information on that certificate",X509SelectionFlag::MultiSelection);
      
      // Create a new AsnEncodedDataCollection object.
      AsnEncodedDataCollection^ asncoll = gcnew AsnEncodedDataCollection;
      for ( int i = 0; i < scollection->Count; i++ )
      {
         
         // Display certificate information.
         Console::ForegroundColor = ConsoleColor::Red;
         Console::WriteLine( L"Certificate name: {0}", scollection[i]->GetName() );
         Console::ResetColor();
         
         // Display extensions information.
         System::Collections::IEnumerator^ myEnum = scollection[i]->Extensions->GetEnumerator();
         while ( myEnum->MoveNext() )
         {
            X509Extension^ extension = safe_cast<X509Extension ^>(myEnum->Current);
            
            // Create an AsnEncodedData object using the extensions information.
            AsnEncodedData^ asndata = gcnew AsnEncodedData( extension->Oid,extension->RawData );
            Console::ForegroundColor = ConsoleColor::Green;
            Console::WriteLine( L"Extension type: {0}", extension->Oid->FriendlyName );
            Console::WriteLine( L"Oid value: {0}", asndata->Oid->Value );
            Console::WriteLine( L"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( L"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( L"First AsnEncodedData in the collection: {0}", asne->Current->Format(true) );
      Console::ResetColor();
      asne->MoveNext();
      Console::ForegroundColor = ConsoleColor::DarkBlue;
      Console::WriteLine( L"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( L"Information could not be written out for this certificate." );
   }

   return 1;
}
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.");
		}
	}
}
Imports System
Imports System.Security.Cryptography
Imports System.Security.Cryptography.X509Certificates



Class AsnEncodedDataSample
   Shared msg As String
   Shared Sub 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.
         Dim store As New X509Store("MY", StoreLocation.CurrentUser)
         store.Open((OpenFlags.ReadOnly Or OpenFlags.OpenExistingOnly))
         Dim collection As X509Certificate2Collection = CType(store.Certificates, X509Certificate2Collection)
         Dim fcollection As X509Certificate2Collection = CType(collection.Find(X509FindType.FindByTimeValid, DateTime.Now, False), X509Certificate2Collection)
         ' Select one or more certificates to display extensions information.
         Dim scollection As X509Certificate2Collection = 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.
         Dim asncoll As New AsnEncodedDataCollection()
         Dim i As Integer
         For i = 0 To scollection.Count - 1
            ' Display certificate information.
	    msg = "Certificate name: "& scollection(i).GetName()
            MsgBox(msg)

            ' Display extensions information.
            Dim extension As X509Extension
            For Each extension In  scollection(i).Extensions
               ' Create an AsnEncodedData object using the extensions information.
               Dim asndata As New AsnEncodedData(extension.Oid, extension.RawData)
	       msg = "Extension type: " & extension.Oid.FriendlyName & Environment.NewLine & "Oid value: " & asndata.Oid.Value _
		& Environment.NewLine & "Raw data length: " & asndata.RawData.Length & Environment.NewLine _
		& asndata.Format(True) & Environment.NewLine
               MsgBox(msg)
		
               ' Add the AsnEncodedData object to the AsnEncodedDataCollection object.
               asncoll.Add(asndata)
            Next extension
         Next i
	 msg = "Number of AsnEncodedData items in the collection: " & asncoll.Count
         MsgBox(msg)         
         store.Close()

         'Create an enumerator for moving through the collection.
         Dim asne As AsnEncodedDataEnumerator = asncoll.GetEnumerator()
         'You must execute a MoveNext() to get to the first item in the collection.
         asne.MoveNext()
         ' Write out AsnEncodedData in the collection.
	 msg = "First AsnEncodedData in the collection: " & asne.Current.Format(True)
	 MsgBox(msg)
	
         
         asne.MoveNext()
	 msg = "Second AsnEncodedData in the collection: " & asne.Current.Format(True)
	 MsgBox(msg)
        
         'Return index in the collection to the beginning.
         asne.Reset()
      Catch 
         MsgBox("Information could not be written out for this certificate.")
      End Try
   End Sub 'Main
End Class 'AsnEncodedDataSample

Poznámky

Po vytvoření čítače MoveNext musí být volána metoda pro přechod enumerátoru na první element kolekce před čtením hodnoty Current vlastnosti; v opačném případě Current vrátí null nebo vyvolá došlo k výjimce.After an enumerator is created, the MoveNext method must be called to advance the enumerator to the first element of the collection before reading the value of the Current property; otherwise, Current returns null or throws an exception.

Current také vrátí hodnotu null nebo vyvolá výjimku, pokud poslední volání MoveNext vrátí false, což znamená, že bylo dosaženo konce kolekce.Current also returns null or throws an exception if the last call to MoveNext returns false, which indicates that the end of the collection has been reached.

Current nepřesouvá pozice čítače výčtu a po sobě jdoucích volání Current vrátit na stejný objekt do MoveNext je volána.Current does not move the position of the enumerator, and consecutive calls to Current return the same object until MoveNext is called.

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