AsnEncodedDataEnumerator.MoveNext Metoda

Definicja

Przestrzeń nazw:

System.Security.Cryptography

Zestaw:

System.Security.Cryptography.dll

Źródło:

AsnEncodedDataEnumerator.cs

Przechodzi do następnego AsnEncodedData obiektu w AsnEncodedDataCollection obiekcie.

public:
 virtual bool MoveNext();

public bool MoveNext ();

abstract member MoveNext : unit -> bool
override this.MoveNext : unit -> bool

Public Function MoveNext () As Boolean

Zwraca

Boolean

true, jeśli moduł wyliczający został pomyślnie zaawansowany do następnego elementu; false, jeśli moduł wyliczający przeszedł koniec kolekcji.

Implementuje

MoveNext()

Wyjątki

InvalidOperationException

Kolekcja została zmodyfikowana po utworzeniu modułu wyliczającego.

Przykłady

W poniższym przykładzie kodu pokazano, jak używać AsnEncodedDataEnumerator klasy .

#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.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
End Class

Uwagi

Po utworzeniu modułu wyliczającego jest on umieszczony przed pierwszym elementem kolekcji, a pierwsze wywołanie MoveNext metody przenosi moduł wyliczający nad pierwszym elementem kolekcji. Kolejne wywołania, aby przejść do MoveNext modułu wyliczającego obok kolejnych elementów.

Po przekazaniu końca kolekcji wywołania w celu MoveNext zwrócenia metody false.

Moduł wyliczający jest ważny tak długo, jak kolekcja pozostaje niezmieniona. Jeśli w kolekcji zostaną wprowadzone zmiany, takie jak dodawanie, modyfikowanie lub usuwanie elementów, moduł wyliczający staje się nieprawidłowy, a następne wywołanie MoveNext metody może zgłosić wyjątek InvalidOperationException.