PublicKey.Key Property

Definition

Namespace:

System.Security.Cryptography.X509Certificates

Assembly:

System.Security.Cryptography.dll

Source:

PublicKey.cs

Caution

PublicKey.Key is obsolete. Use the appropriate method to get the public key, such as GetRSAPublicKey.

Gets an RSA derived object or a DSA derived object representing the public key.

public:
 property System::Security::Cryptography::AsymmetricAlgorithm ^ Key { System::Security::Cryptography::AsymmetricAlgorithm ^ get(); };

[System.Obsolete("PublicKey.Key is obsolete. Use the appropriate method to get the public key, such as GetRSAPublicKey.", DiagnosticId="SYSLIB0027", UrlFormat="https://aka.ms/dotnet-warnings/{0}")]
public System.Security.Cryptography.AsymmetricAlgorithm Key { get; }

[<System.Obsolete("PublicKey.Key is obsolete. Use the appropriate method to get the public key, such as GetRSAPublicKey.", DiagnosticId="SYSLIB0027", UrlFormat="https://aka.ms/dotnet-warnings/{0}")>]
member this.Key : System.Security.Cryptography.AsymmetricAlgorithm

Public ReadOnly Property Key As AsymmetricAlgorithm

Property Value

AsymmetricAlgorithm

An AsymmetricAlgorithm object representing the public key.

Attributes

ObsoleteAttribute

Exceptions

NotSupportedException

The key algorithm is not supported.

Examples

The following code example opens the current user certificate store, selects only active certificates, and then allows the user to select one or more certificates. The example then writes certificate information to the console.

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

using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Security::Permissions;
using namespace System::IO;
using namespace System::Security::Cryptography::X509Certificates;
int main()
{
   try
   {
      X509Store ^ store = gcnew X509Store( "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 ));
      X509Certificate2Collection ^ scollection = X509Certificate2UI::SelectFromCollection(fcollection, "Test Certificate Select","Select a certificate from the following list to get information on that certificate",X509SelectionFlag::MultiSelection);
      Console::WriteLine( "Number of certificates: {0}{1}", scollection->Count, Environment::NewLine );
      System::Collections::IEnumerator^ myEnum = scollection->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         X509Certificate2 ^ x509 = safe_cast<X509Certificate2 ^>(myEnum->Current);
         array<Byte>^rawdata = x509->RawData;
         Console::WriteLine( "Content Type: {0}{1}", X509Certificate2::GetCertContentType( rawdata ), Environment::NewLine );
         Console::WriteLine( "Friendly Name: {0}{1}", x509->FriendlyName, Environment::NewLine );
         Console::WriteLine( "Certificate Verified?: {0}{1}", x509->Verify(), Environment::NewLine );
         Console::WriteLine( "Simple Name: {0}{1}", x509->GetNameInfo( X509NameType::SimpleName, true ), Environment::NewLine );
         Console::WriteLine( "Signature Algorithm: {0}{1}", x509->SignatureAlgorithm->FriendlyName, Environment::NewLine );
         Console::WriteLine( "Private Key: {0}{1}", x509->PrivateKey->ToXmlString( false ), Environment::NewLine );
         Console::WriteLine( "Public Key: {0}{1}", x509->PublicKey->Key->ToXmlString( false ), Environment::NewLine );
         Console::WriteLine( "Certificate Archived?: {0}{1}", x509->Archived, Environment::NewLine );
         Console::WriteLine( "Length of Raw Data: {0}{1}", x509->RawData->Length, Environment::NewLine );
         x509->Reset();
      }
      store->Close();
   }
   catch ( CryptographicException^ ) 
   {
      Console::WriteLine( "Information could not be written out for this certificate." );
   }

}

using System;
using System.Security.Cryptography;
using System.Security.Permissions;
using System.IO;
using System.Security.Cryptography.X509Certificates;

class CertSelect
{
    static void Main()
    {
        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);
        X509Certificate2Collection scollection = X509Certificate2UI.SelectFromCollection(fcollection, "Test Certificate Select","Select a certificate from the following list to get information on that certificate",X509SelectionFlag.MultiSelection);
        Console.WriteLine("Number of certificates: {0}{1}",scollection.Count,Environment.NewLine);

        foreach (X509Certificate2 x509 in scollection)
        {
            try
            {
                byte[] rawdata = x509.RawData;
                Console.WriteLine("Content Type: {0}{1}",X509Certificate2.GetCertContentType(rawdata),Environment.NewLine);
                Console.WriteLine("Friendly Name: {0}{1}",x509.FriendlyName,Environment.NewLine);
                Console.WriteLine("Certificate Verified?: {0}{1}",x509.Verify(),Environment.NewLine);
                Console.WriteLine("Simple Name: {0}{1}",x509.GetNameInfo(X509NameType.SimpleName,true),Environment.NewLine);
                Console.WriteLine("Signature Algorithm: {0}{1}",x509.SignatureAlgorithm.FriendlyName,Environment.NewLine);
                Console.WriteLine("Public Key: {0}{1}",x509.PublicKey.Key.ToXmlString(false),Environment.NewLine);
                Console.WriteLine("Certificate Archived?: {0}{1}",x509.Archived,Environment.NewLine);
                Console.WriteLine("Length of Raw Data: {0}{1}",x509.RawData.Length,Environment.NewLine);
                X509Certificate2UI.DisplayCertificate(x509);
                x509.Reset();
            }
            catch (CryptographicException)
            {
                Console.WriteLine("Information could not be written out for this certificate.");
            }
        }
        store.Close();
    }
}

Imports System.Security.Cryptography
Imports System.Security.Permissions
Imports System.IO
Imports System.Security.Cryptography.X509Certificates

Class CertSelect

    Shared Sub Main()

        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)
        Dim scollection As X509Certificate2Collection = X509Certificate2UI.SelectFromCollection(fcollection, "Test Certificate Select", "Select a certificate from the following list to get information on that certificate", X509SelectionFlag.MultiSelection)
        Console.WriteLine("Number of certificates: {0}{1}", scollection.Count, Environment.NewLine)
         
        For Each x509 As X509Certificate2 In scollection
            Try
                Dim rawdata As Byte() = x509.RawData
                Console.WriteLine("Content Type: {0}{1}", X509Certificate2.GetCertContentType(rawdata), Environment.NewLine)
                Console.WriteLine("Friendly Name: {0}{1}", x509.FriendlyName, Environment.NewLine)
                Console.WriteLine("Certificate Verified?: {0}{1}", x509.Verify(), Environment.NewLine)
                Console.WriteLine("Simple Name: {0}{1}", x509.GetNameInfo(X509NameType.SimpleName, True), Environment.NewLine)
                Console.WriteLine("Signature Algorithm: {0}{1}", x509.SignatureAlgorithm.FriendlyName, Environment.NewLine)
                Console.WriteLine("Public Key: {0}{1}", x509.PublicKey.Key.ToXmlString(False), Environment.NewLine)
                Console.WriteLine("Certificate Archived?: {0}{1}", x509.Archived, Environment.NewLine)
                Console.WriteLine("Length of Raw Data: {0}{1}", x509.RawData.Length, Environment.NewLine)
                X509Certificate2UI.DisplayCertificate(x509)
                x509.Reset()         
             Catch cExcept As CryptographicException
                 Console.WriteLine("Information could not be written out for this certificate.")
             End Try
        Next x509

        store.Close()
    End Sub
End Class

Remarks

This property returns the public key. Both RSA and DSA keys are supported. Call this property to obtain a certificate's public key. Repeated calls to this property will return the same key.