AsnEncodedDataEnumerator.MoveNext 方法

定義

命名空間:

System.Security.Cryptography

組件:

System.Security.Cryptography.dll

來源:

AsnEncodedDataEnumerator.cs

前進到 AsnEncodedData 物件中的下一個 AsnEncodedDataCollection 物件。

public:
 virtual bool MoveNext();

public bool MoveNext ();

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

Public Function MoveNext () As Boolean

傳回

Boolean

如果列舉值成功前移至下一個項目，則為 true，如果列舉值已超過集合的結尾，則為 false。

實作

MoveNext()

例外狀況

InvalidOperationException

建立列舉值之後，集合已修改。

範例

下列程式碼範例示範如何使用 AsnEncodedDataEnumerator 類別。

#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

備註

建立列舉值之後，它會放置在集合的第一個專案之前，而對 方法的第一次呼叫 MoveNext 會將列舉值移至集合的第一個專案上。 後續呼叫，以 MoveNext 將列舉值前進到後續元素之後。

傳遞集合結尾之後，呼叫 以傳 MoveNext 回 false。

只要集合維持不變，列舉值就有效。 如果對集合進行變更，例如新增、修改或刪除專案，列舉值就會變成無效，而下一個InvalidOperationException呼叫MoveNext可以擲回 。