AsymmetricAlgorithm AsymmetricAlgorithm AsymmetricAlgorithm AsymmetricAlgorithm Class

Definice

Představuje abstraktní základní třída, ze kterého musí dědit všechny implementace asymetrické algoritmy.Represents the abstract base class from which all implementations of asymmetric algorithms must inherit.

public ref class AsymmetricAlgorithm abstract : IDisposable
[System.Runtime.InteropServices.ComVisible(true)]
public abstract class AsymmetricAlgorithm : IDisposable
type AsymmetricAlgorithm = class
    interface IDisposable
Public MustInherit Class AsymmetricAlgorithm
Implements IDisposable
Dědičnost
AsymmetricAlgorithmAsymmetricAlgorithmAsymmetricAlgorithmAsymmetricAlgorithm
Odvozené
Atributy
Implementuje

Příklady

Následující příklad kódu ukazuje, jak implementovat vlastní asymetrického algoritmu zděděno z AsymmetricAlgorithm třídy.The following code example demonstrates how to implement a custom asymmetric algorithm inherited from the AsymmetricAlgorithm class. Další třídy dostane ukazují, jak používat vlastní třídy.An additional class is provided to demonstrate how to use the custom class.

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

using namespace System;
using namespace System::Xml;
using namespace System::Text;
using namespace System::Security::Cryptography;
using namespace System::Reflection;

[assembly: AssemblyKeyFile("CustomCrypto.snk")];
[assembly: AssemblyVersion("1.0.0.0")];
[assembly: CLSCompliant(true)];
namespace Contoso
{
    // Define a CustomCrypto class that inherits from the AsymmetricAlgorithm
    // class.
    public ref class CustomCrypto :
        public System::Security::Cryptography::AsymmetricAlgorithm
        {
            // Declare local member variables.
        private:
            CspParameters^ cryptoServiceParameters;
            array<KeySizes^>^ customValidKeySizes;

            // Initialize a CustomCrypto with the default key size of 8.
        public:
            CustomCrypto()
            {
                customValidKeySizes = 
                    gcnew array<KeySizes^>{gcnew KeySizes(8, 64, 8)};
                this->KeySize = 8;
            }

            // Initialize a CustomCrypto with the specified key size.
        public:
            CustomCrypto(int keySize)
            {
                customValidKeySizes = 
                    gcnew array<KeySizes^>{gcnew KeySizes(8, 64, 8)};
                this->KeySize = keySize;
            }

            // Accessor function for keySizes member variable.
        public:
            property array<KeySizes^>^ LegalKeySizes
            {
                virtual array<KeySizes^>^ get() override
                {
                    return (array<KeySizes^>^)customValidKeySizes->Clone();
                }
            }

            // Modify the KeySizeValue property inherited from the Asymmetric
            // class. Prior to setting the value, ensure it falls within the
            // range identified in the local keySizes member variable.
        public:
            property int KeySize
            {
                virtual int get() override
                {
                    return KeySizeValue;
                }

                virtual void set(int value) override
                {
                    for (int i = 0; i < customValidKeySizes->Length; i++)
                    {
                        if (customValidKeySizes[i]->SkipSize == 0)
                        {
                            if (customValidKeySizes[i]->MinSize == value)
                            {
                                KeySizeValue = value;
                                return;
                            }
                        }
                        else
                        {
                            for (int j = customValidKeySizes[i]->MinSize;
                                j <= customValidKeySizes[i]->MaxSize;
                                j += customValidKeySizes[i]->SkipSize)
                            {
                                if (j == value)
                                {
                                    KeySizeValue = value;
                                    return;
                                }
                            }
                        }
                    }

                    // If the key does not fall within the range identified
                    // in the keySizes member variable, throw an exception.
                    throw gcnew CryptographicException("Invalid key size.");
                }
            }

            // Initialize the parameters with default values.
        public:
            void InitializeParameters()
            {
                cryptoServiceParameters = gcnew CspParameters();
                cryptoServiceParameters->ProviderName = "Contoso";
                cryptoServiceParameters->KeyContainerName = "SecurityBin1";
                cryptoServiceParameters->KeyNumber = 1;
                cryptoServiceParameters->ProviderType = 2;
            }

            // Parse specified xmlString for values to populate the CspParams
            // Expected XML schema:
            //      <ProviderName></ProviderName>
            //      <KeyContainerName></KeyContainerName>
            //      <KeyNumber></KeyNumber>
            //      <ProviderType></ProviderType>
        public:
            virtual void FromXmlString(String^ xmlString) override 
            {
                if (xmlString != nullptr)
                {
                    XmlDocument^ document = gcnew XmlDocument();
                    document->LoadXml(xmlString);
                    XmlNode^ firstNode = document->FirstChild;
                    XmlNodeList^ nodeList;

                    // Assemble parameters from values in each XML element.
                    cryptoServiceParameters = gcnew CspParameters();

                    // KeyContainerName is optional.
                    nodeList = 
                        document->GetElementsByTagName("KeyContainerName");
                    if (nodeList->Count > 0)
                    {
                        cryptoServiceParameters->KeyContainerName =
                            nodeList->Item(0)->InnerText;
                    }

                    // KeyNumber is optional.
                    nodeList = document->GetElementsByTagName("KeyNumber");
                    if (nodeList->Count > 0)
                    {
                        cryptoServiceParameters->KeyNumber =
                            Int32::Parse(nodeList->Item(0)->InnerText);
                    }

                    // ProviderName is optional.
                    nodeList = document->GetElementsByTagName("ProviderName");
                    if (nodeList->Count > 0)
                    {
                        cryptoServiceParameters->ProviderName =
                            nodeList->Item(0)->InnerText;
                    }

                    // ProviderType is optional.
                    nodeList = document->GetElementsByTagName("ProviderType");
                    if (nodeList->Count > 0)
                    {
                        cryptoServiceParameters->ProviderType =
                            Int32::Parse(nodeList->Item(0)->InnerText);
                    }
                }
                else
                {
                    throw gcnew ArgumentNullException("xmlString");
                }
            }

            // Create an XML string representation of the parameters in the
            // current customCrypto object.
        public:
            virtual String^ ToXmlString(bool includePrivateParameters) override
            {
                String^ keyContainerName = "";
                String^ keyNumber = "";
                String^ providerName = "";
                String^ providerType = "";

                if (cryptoServiceParameters != nullptr)
                {
                    keyContainerName = 
                        cryptoServiceParameters->KeyContainerName;
                    keyNumber = cryptoServiceParameters->KeyNumber.ToString();
                    providerName = cryptoServiceParameters->ProviderName;
                    providerType = 
                        cryptoServiceParameters->ProviderType.ToString();
                }

                StringBuilder^ sb = gcnew StringBuilder();
                sb->Append("<CustomCryptoKeyValue>");

                sb->Append("<KeyContainerName>");
                sb->Append(keyContainerName);
                sb->Append("</KeyContainerName>");

                sb->Append("<KeyNumber>");
                sb->Append(keyNumber);
                sb->Append("</KeyNumber>");

                sb->Append("<ProviderName>");
                sb->Append(providerName);
                sb->Append("</ProviderName>");

                sb->Append("<ProviderType>");
                sb->Append(providerType);
                sb->Append("</ProviderType>");

                sb->Append("</CustomCryptoKeyValue>");
                return(sb->ToString());
            }

            // Return the name for the key exchange algorithm.
        public:
            property String^ KeyExchangeAlgorithm 
            {
                virtual String^ get() override
                {
                    return "RSA-PKCS1-KeyEx";
                }
            }

            // Retrieves the name of the signature alogrithm.
        public:
            property String^ SignatureAlgorithm
            {
                virtual String^ get() override
                {
                    return "http://www.w3.org/2000/09/xmldsig#rsa-sha1";
                }
            }

            // Required member for implementing the AsymmetricAlgorithm class.
		protected:
			virtual ~CustomCrypto()
			{
			}

            // Call the Create method using the CustomCrypto assembly name.
            // The create function attempts to create a CustomCrypto 
            // object using the assembly name. This functionality requires 
            // modification of the machine.config file. Add the following 
            // section to the configuration element and modify the values 
            // of the cryptoClass to reflect what isinstalled 
            // in your machines GAC.
            //        <cryptoClass CustomCrypto="Contoso.CustomCrypto,
            //          CustomCrypto,
            //          Culture=neutral,
            //          PublicKeyToken=fdb9f9c4851028bf,
            //          Version=1.0.1448.27640" />
            //      <nameEntry name="Contoso.CustomCrypto" 
            //         class="CustomCrypto" />
            //      <nameEntry name="CustomCrypto" class="CustomCrypto" />

        public:
            static CustomCrypto^ Create() 
            {
                return Create("CustomCrypto");
            }

            // Create a CustomCrypto object by calling CrytoConfig's
            // CreateFromName method and casting the type to CustomCrypto.
            // The create function attempts to create a CustomCrypto object 
            // using the assembly name. This functionality requires 
            // modification of the machine.config file. Add the following 
            // section to the configuration element and modify the values 
            // of the cryptoClass to reflect what is installed 
            // in your machines GAC.
            //       <cryptoClass CustomCrypto="Contoso.CustomCrypto,
            //         CustomCrypto,
            //         Culture=neutral,
            //         PublicKeyToken=fdb9f9c4851028bf,
            //         Version=1.0.1448.27640" />
            //     <nameEntry name="Contoso.CustomCrypto" 
            //        class="CustomCrypto" />
            //     <nameEntry name="CustomCrypto" class="CustomCrypto" />

        public:
            static CustomCrypto^ Create(String^ algorithmName) 
            {
                return (CustomCrypto^) 
                    CryptoConfig::CreateFromName(algorithmName);
            }
        };
}
using System;
using System.Xml;
using System.Text;
using System.Security.Cryptography;
using System.Reflection;

[assembly: AssemblyKeyFile("CustomCrypto.snk")]
[assembly: AssemblyVersion("1.0.0.0")]
[assembly: CLSCompliant(true)]
namespace Contoso
{
    // Define a CustomCrypto class that inherits from the AsymmetricAlgorithm
    // class.
    public class CustomCrypto : 
        System.Security.Cryptography.AsymmetricAlgorithm
    {
        // Declare local member variables.
        private CspParameters cspParameters;
        private readonly KeySizes[] keySizes = {new KeySizes(8, 64, 8)};

        // Initialize a CustomCrypto with the default key size of 8.
        public CustomCrypto()
        {
            this.KeySize = 8;
        }

        // Initialize a CustomCrypto with the specified key size.
        public CustomCrypto(int keySize)
        {
            this.KeySize = keySize;
        }

        // Accessor function for keySizes member variable.
        public override KeySizes[] LegalKeySizes 
        { 
            get { return (KeySizes[])keySizes.Clone(); }
        }

        // Modify the KeySizeValue property inherited from the Asymmetric
        // class. Prior to setting the value, ensure it falls within the
        // range identified in the local keySizes member variable.
        public override int KeySize 
        {
            get { return KeySizeValue; }
            set
            {
                for (int i=0; i < keySizes.Length; i++)
                {
                    if (keySizes[i].SkipSize == 0) 
                    {
                        if (keySizes[i].MinSize == value)
                        {
                            KeySizeValue = value;
                            return;
                        }
                    }
                    else
                    {
                        for (int j = keySizes[i].MinSize;
                            j <= keySizes[i].MaxSize;
                            j += keySizes[i].SkipSize)
                        {
                            if (j == value)
                            {
                                KeySizeValue = value;
                                return;
                            }
                        }
                    }
                }

                // If the key does not fall within the range identified 
                // in the keySizes member variable, throw an exception.
                throw new CryptographicException("Invalid key size.");
            }
        }

        // Initialize the parameters with default values.
        public void InitializeParameters()
        {
            cspParameters = new CspParameters();
            cspParameters.ProviderName = "Contoso";
            cspParameters.KeyContainerName = "SecurityBin1";
            cspParameters.KeyNumber = 1;
            cspParameters.ProviderType = 2;
        }

        // Parse specified xmlString for values to populate the CspParams
        // Expected XML schema:
        //      <ProviderName></ProviderName>
        //      <KeyContainerName></KeyContainerName>
        //      <KeyNumber></KeyNumber>
        //      <ProviderType></ProviderType>
        public override void FromXmlString(string xmlString)
        {
            if (xmlString != null)
            {
                XmlDocument doc = new XmlDocument();
                doc.LoadXml(xmlString);
                XmlNode firstNode = doc.FirstChild;
                XmlNodeList nodeList;

                // Assemble parameters from values in each XML element.
                cspParameters = new CspParameters();

                // KeyContainerName is optional.
                nodeList = doc.GetElementsByTagName("KeyContainerName");
                string keyName = nodeList.Item(0).InnerText;
                if (keyName != null) 
                {
                    cspParameters.KeyContainerName = keyName;
                }

                // KeyNumber is optional.
                nodeList = doc.GetElementsByTagName("KeyNumber");
                string keyNumber = nodeList.Item(0).InnerText;
                if (keyNumber != null) 
                {
                    cspParameters.KeyNumber = Int32.Parse(keyNumber);
                }

                // ProviderName is optional.
                nodeList = doc.GetElementsByTagName("ProviderName");
                string providerName = nodeList.Item(0).InnerText;
                if (providerName != null) 
                {
                    cspParameters.ProviderName = providerName;
                }

                // ProviderType is optional.
                nodeList = doc.GetElementsByTagName("ProviderType");
                string providerType = nodeList.Item(0).InnerText;
                if (providerType != null) 
                {
                    cspParameters.ProviderType = Int32.Parse(providerType);
                }
            }
            else
            {
                throw new ArgumentNullException("xmlString");
            }
        }

        // Create an XML string representation of the parameters in the
        // current customCrypto object.
        public override string ToXmlString(bool includePrivateParameters)
        {
            string keyContainerName = "";
            string keyNumber = "";
            string providerName = "";
            string providerType = "";

            if (cspParameters != null)
            {
                keyContainerName = cspParameters.KeyContainerName;
                keyNumber = cspParameters.KeyNumber.ToString();
                providerName = cspParameters.ProviderName;
                providerType = cspParameters.ProviderType.ToString();
            }

            StringBuilder sb = new StringBuilder();
            sb.Append("<CustomCryptoKeyValue>");

            sb.Append("<KeyContainerName>");
            sb.Append(keyContainerName);
            sb.Append("</KeyContainerName>");

            sb.Append("<KeyNumber>");
            sb.Append(keyNumber);
            sb.Append("</KeyNumber>");

            sb.Append("<ProviderName>");
            sb.Append(providerName);
            sb.Append("</ProviderName>");

            sb.Append("<ProviderType>");
            sb.Append(providerType);
            sb.Append("</ProviderType>");

            sb.Append("</CustomCryptoKeyValue>");
            return(sb.ToString());
        }

        // Return the name for the key exchange algorithm.
        public override string KeyExchangeAlgorithm
        {
            get {return "RSA-PKCS1-KeyEx";}
        }

        // Retrieves the name of the signature alogrithm.
        public override string SignatureAlgorithm 
        {
            get {return "http://www.w3.org/2000/09/xmldsig#rsa-sha1";}
        }

        // Required member for implementing the AsymmetricAlgorithm class.
        protected override void Dispose(bool disposing) {}

        // Call the Create method using the CustomCrypto assembly name.
        // The create function attempts to create a CustomCrypto object using
        // the assembly name. This functionality requires modification of the
        // machine.config file. Add the following section to the configuration
        // element and modify the values of the cryptoClass to reflect what is
        // installed in your machines GAC.
        //        <cryptoClass CustomCrypto="Contoso.CustomCrypto, 
        //          CustomCrypto, 
        //          Culture=neutral, 
        //          PublicKeyToken=fdb9f9c4851028bf, 
        //          Version=1.0.1448.27640" />
        //      <nameEntry name="Contoso.CustomCrypto" class="CustomCrypto" />
        //      <nameEntry name="CustomCrypto" class="CustomCrypto" />
        new static public CustomCrypto Create() 
        {
            return Create("CustomCrypto");
        }

        // Create a CustomCrypto object by calling CrytoConfig's
        // CreateFromName method and casting the type to CustomCrypto.
        // The create function attempts to create a CustomCrypto object using
        // the assembly name. This functionality requires modification of the
        // machine.config file. Add the following section to the configuration
        // element and modify the values of the cryptoClass to reflect what is
        // installed in your machines GAC.
        //       <cryptoClass CustomCrypto="Contoso.CustomCrypto, 
        //         CustomCrypto, 
        //         Culture=neutral, 
        //         PublicKeyToken=fdb9f9c4851028bf, 
        //         Version=1.0.1448.27640" />
        //     <nameEntry name="Contoso.CustomCrypto" class="CustomCrypto" />
        //     <nameEntry name="CustomCrypto" class="CustomCrypto" />
        new static public CustomCrypto Create(String algorithmName) 
        {
            return (CustomCrypto) CryptoConfig.CreateFromName(algorithmName);
        }
    }
    class CustomCryptoImpl
    {
        [STAThread]
        static void Main(string[] args)
        {
            // Construct a CustomCrypto object and initialize its
            // CspParameters.
            CustomCrypto customCrypto = new CustomCrypto();
            customCrypto.InitializeParameters();

            // Display properties of the current customCrypto object.
            Console.WriteLine("*** CustomCrypto created with default " + 
                "parameters:");
            DisplayProperties(customCrypto);

            // Release all the resources used by this instance of 
            // CustomCrytpo.
            customCrypto.Clear();

            customCrypto = new CustomCrypto(64);
            // Create new parameters and set them by using the FromXmlString
            // method.
            string parameterXml = "<CustomCryptoKeyValue>";
            parameterXml += "<ProviderName>Contoso</ProviderName>";
            parameterXml += "<KeyContainerName>SecurityBin2";
            parameterXml += "</KeyContainerName>";
            parameterXml += "<KeyNumber>1</KeyNumber>";
            parameterXml += "<ProviderType>2</ProviderType>";
            parameterXml += "</CustomCryptoKeyValue>";
            customCrypto.FromXmlString(parameterXml);

            // Display the properties of a customCrypto object created with
            // custom parameters.
            Console.WriteLine("\n*** " + 
                "CustomCrypto created with custom parameters:");
            DisplayProperties(customCrypto);

            // Create an object by using the assembly name.
            try
            {
                CustomCrypto myCryptoA = CustomCrypto.Create("CustomCrypto");
                if (myCryptoA != null)
                {
                    Console.Write("\n*** " + 
                        "Successfully created CustomCrytpo from");
                    Console.WriteLine(" the Create method.");

                    DisplayProperties(myCryptoA);
                }
                else
                {
                    Console.Write("Unable to create CustomCrytpo from ");
                    Console.WriteLine(" the Create method.");
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            
            Console.WriteLine("This sample completed successfully; " +
                "press Enter to exit.");
            Console.ReadLine();
        }
        // Display the properties of the specified CustomCrypto object to the
        // console.
        public static void DisplayProperties(CustomCrypto customCrypto)
        {
            try
            {
                // Retrieve the class description for the customCrypto object.
                string classDescription = customCrypto.ToString();

                Console.WriteLine(classDescription);
                Console.Write("KeyExchangeAlgorithm: ");
                Console.WriteLine(customCrypto.KeyExchangeAlgorithm);
                Console.Write("SignatureAlgorithm: ");
                Console.WriteLine(customCrypto.SignatureAlgorithm);
                Console.WriteLine("KeySize: " + customCrypto.KeySize);
                Console.WriteLine("Parameters described in Xml format:");
                Console.WriteLine(customCrypto.ToXmlString(true));

                // Display the MinSize, MaxSize, and SkipSize properties of 
                // each KeySize item in the local keySizes member variable.
                KeySizes[] legalKeySizes = customCrypto.LegalKeySizes;
                if (legalKeySizes.Length > 0)
                {
                    for (int i=0; i < legalKeySizes.Length; i++)
                    {
                        Console.Write("Keysize" + i + " min, max, step: ");
                        Console.Write(legalKeySizes[i].MinSize + ", ");
                        Console.Write(legalKeySizes[i].MaxSize + ", ");
                        Console.WriteLine(legalKeySizes[i].SkipSize + ", ");
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Caught unexpected exception: " + 
                    ex.ToString());
            }
        }
    }
}
//
// This sample produces the following output:
//
// *** CustomCrypto created with default parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 8
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// 
// *** CustomCrypto created with custom parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 64
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// Unable to create CustomCrytpo from  the Create method
// This sample completed successfully; press Exit to continue.
Imports System
Imports System.Xml
Imports System.Text
Imports System.Security.Cryptography
Imports System.Reflection

<Assembly: AssemblyKeyFile("CustomCrypto.snk")> 
<Assembly: AssemblyVersion("1.0.0.0")> 
<Assembly: CLSCompliant(True)> 
Namespace Contoso
    ' Define a vbCustomCrypto class that inherits from the AsymmetricAlgorithm
    ' class.
    Class vbCustomCrypto
        Inherits System.Security.Cryptography.AsymmetricAlgorithm

        ' Declare local member variables.
        Private cspParameters As CspParameters
        Private ReadOnly keySizes() As keySizes = {New keySizes(8, 64, 8)}

        ' Initialize a vbCustomCrypto with the default key size of 8.
        Public Sub New()
            Me.KeySize = 8
        End Sub

        ' Initialize a vbCustomCrypto with the specified key size.
        Public Sub New(ByVal keySize As Integer)
            Me.KeySize = keySize
        End Sub

        ' Modify the KeySizeValue property inherited from the Asymmetric
        ' class. Prior to setting the value, ensure it falls within the
        ' range identified in the local keySizes member variable.
        Public Overrides Property KeySize() As Integer
            Get
                Return KeySizeValue
            End Get
            Set(ByVal Value As Integer)
                For i As Int16 = 0 To keySizes.Length - 1 Step i
                    If (keySizes(i).SkipSize.Equals(0)) Then
                        If (keySizes(i).MinSize.Equals(Value)) Then
                            KeySizeValue = Value
                            Return
                        End If
                    Else
                        For j As Integer = keySizes(i).MinSize _
                            To keySizes(i).MaxSize _
                            Step keySizes(i).SkipSize
                            If (j.Equals(Value)) Then
                                KeySizeValue = Value
                                Return
                            End If
                        Next
                    End If
                Next
                ' If the key does not fall within the range identified 
                ' in the keySizes member variable, throw an exception.
                Throw New CryptographicException("Invalid key size.")
            End Set
        End Property
        ' Accessor function for keySizes member variable.
        public Overrides Readonly Property LegalKeySizes as KeySizes()
            Get
                Return keySizes
            End Get
        End Property
        ' Initialize the parameters with default values.
        Public Sub InitializeParameters()
            cspParameters = New CspParameters
            cspParameters.ProviderName = "Contoso"
            cspParameters.KeyContainerName = "SecurityBin1"
            cspParameters.KeyNumber = 1
            cspParameters.ProviderType = 2
        End Sub

        ' Parse specified xmlString for values to populate the CspParams
        ' Expected XML schema:
        '      <ProviderName></ProviderName>
        '      <KeyContainerName></KeyContainerName>
        '      <KeyNumber></KeyNumber>
        '      <ProviderType></ProviderType>
        Public Overrides Sub FromXmlString(ByVal xmlString As String)
            If Not xmlString Is Nothing Then
                Dim doc As New XmlDocument
                doc.LoadXml(xmlString)
                Dim firstNode As XmlNode = doc.FirstChild
                Dim nodeList As XmlNodeList

                ' Assemble parameters from values in each XML element.
                cspParameters = New CspParameters

                ' KeyContainerName is optional.
                nodeList = doc.GetElementsByTagName("KeyContainerName")
                Dim keyName As String = nodeList.Item(0).InnerText
                If Not keyName Is Nothing Then
                    cspParameters.KeyContainerName = keyName
                End If

                ' KeyNumber is optional.
                nodeList = doc.GetElementsByTagName("KeyNumber")
                Dim keyNumber As String = nodeList.Item(0).InnerText
                If Not keyNumber Is Nothing Then
                    cspParameters.KeyNumber = Int32.Parse(keyNumber)
                End If

                ' ProviderName is optional.
                nodeList = doc.GetElementsByTagName("ProviderName")
                Dim providerName As String = nodeList.Item(0).InnerText
                If Not providerName Is Nothing Then
                    cspParameters.ProviderName = providerName
                End If

                ' ProviderType is optional.
                nodeList = doc.GetElementsByTagName("ProviderType")
                Dim providerType As String = nodeList.Item(0).InnerText
                If Not providerType Is Nothing Then
                    cspParameters.ProviderType = Int32.Parse(providerType)
                End If
            Else
                Throw New ArgumentNullException("xmlString")
            End If
        End Sub

        ' Create an XML string representation of the parameters in the current
        ' vbCustomCrypto object.
        Public Overrides Function ToXmlString( _
            ByVal includePrivateParameters As Boolean) As String

            Dim keyContainerName As String = ""
            Dim keyNumber As String = ""
            Dim providerName As String = ""
            Dim providerType As String = ""

            If Not cspParameters Is Nothing Then
                keyContainerName = cspParameters.KeyContainerName
                keyNumber = cspParameters.KeyNumber.ToString()
                providerName = cspParameters.ProviderName
                providerType = cspParameters.ProviderType.ToString()
            End If

            Dim xmlBuilder As New StringBuilder
            xmlBuilder.Append("<CustomCryptoKeyValue>")

            xmlBuilder.Append("<KeyContainerName>")
            xmlBuilder.Append(keyContainerName)
            xmlBuilder.Append("</KeyContainerName>")

            xmlBuilder.Append("<KeyNumber>")
            xmlBuilder.Append(keyNumber)
            xmlBuilder.Append("</KeyNumber>")

            xmlBuilder.Append("<ProviderName>")
            xmlBuilder.Append(providerName)
            xmlBuilder.Append("</ProviderName>")

            xmlBuilder.Append("<ProviderType>")
            xmlBuilder.Append(providerType)
            xmlBuilder.Append("</ProviderType>")

            xmlBuilder.Append("</CustomCryptoKeyValue>")
            Return (xmlBuilder.ToString())
        End Function

        ' Return the name for the key exchange algorithm.
        Public Overrides ReadOnly Property KeyExchangeAlgorithm() As String
            Get
                Return "RSA-PKCS1-KeyEx"
            End Get
        End Property

        ' Retrieves the name of the signature alogrithm.
        Public Overrides ReadOnly Property SignatureAlgorithm() As String
            Get
                Return "http://www.w3.org/2000/09/xmldsig#rsa-sha1"
            End Get
        End Property

        ' Required member for implementing the AsymmetricAlgorithm class.
        Protected Overrides Sub Dispose(ByVal disposing As Boolean)

        End Sub

        ' The create function attempts to create a vbCustomCrypto object using
        ' the assembly name. This functionality requires modification of the
        ' machine.config file. Add the following section to the configuration
        ' element and modify the values of the cryptoClass to reflect what is
        ' installed in your machines GAC.
        '          <cryptoClass vbCustomCrypto="Contoso.vbCustomCrypto, 
        '            vbCustomCrypto, 
        '            Culture=neutral, 
        '            PublicKeyToken=fdb9f9c4851028bf, 
        '            Version=1.0.1448.27640" />
        '        <nameEntry name="Contoso.vbCustomCrypto" 
        '                   class="vbCustomCrypto" />
        '        <nameEntry name="vbCustomCrypto" class="vbCustomCrypto" />
        Public Shadows Function Create() As vbCustomCrypto
            Return Create("vbCustomCrypto")
        End Function

        ' Create a CustomCrypto object by calling CrytoConfig's
        ' CreateFromName method and casting the type to CustomCrypto.
        ' The create function attempts to create a vbCustomCrypto object using
        ' the assembly name. This functionality requires modification of the
        ' machine.config file. Add the following section to the configuration
        ' element and modify the values of the cryptoClass to reflect what is
        ' installed in your machines GAC.
        '          <cryptoClass vbCustomCrypto="Contoso.vbCustomCrypto, 
        '            vbCustomCrypto, 
        '            Culture=neutral, 
        '            PublicKeyToken=fdb9f9c4851028bf, 
        '            Version=1.0.1448.27640" />
        '        <nameEntry name="Contoso.vbCustomCrypto" 
        '                   class="vbCustomCrypto" />
        '        <nameEntry name="vbCustomCrypto" class="vbCustomCrypto" />
        Public Shadows Function Create( _
            ByVal algorithmName As String) As vbCustomCrypto

            Return CType( _
                CryptoConfig.CreateFromName(algorithmName), _
                vbCustomCrypto)

        End Function
    End Class
    Class Form1
        Inherits System.Windows.Forms.Form

        ' Event handler for Run button.
        Private Sub Button1_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button1.Click

            tbxOutput.Cursor = Cursors.WaitCursor
            tbxOutput.Text = ""

            ' Construct a CustomCrypto object and initialize its
            ' CspParameters.
            Dim customCrypto As New Contoso.vbCustomCrypto
            customCrypto.InitializeParameters()

            ' Display properties of the current vbCustomCrypto object.
            WriteLine("*** CustomCrypto created with default parameters:")
            DisplayProperties(customCrypto)

            ' Release all the resources used by this instance of CustomCrytpo.
            customCrypto.Clear()

            customCrypto = New Contoso.vbCustomCrypto(64)
            ' Create new parameters and set them by using the
            ' FromXmlString method.
            Dim parameterXml As String = "<CustomCryptoKeyValue>"
            parameterXml += "<ProviderName>Contoso</ProviderName>"
            parameterXml += "<KeyContainerName>SecurityBin2"
            parameterXml += "</KeyContainerName>"
            parameterXml += "<KeyNumber>1</KeyNumber>"
            parameterXml += "<ProviderType>2</ProviderType>"
            parameterXml += "</CustomCryptoKeyValue>"
            customCrypto.FromXmlString(parameterXml)

            ' Display the properties of a customCrypto object created with
            ' custom parameters.
            WriteLine(vbCrLf + "*** " + _
                "CustomCrypto created with custom parameters:")
            DisplayProperties(customCrypto)

            ' Create an object by using the assembly name.
            Try
                Dim createdCrypto As Contoso.vbCustomCrypto
                createdCrypto = customCrypto.Create("vbCustomCrypto")

                If (Not createdCrypto Is Nothing) Then
                    Write(vbCrLf + "*** Successfully created vbCustomCrytpo ")
                    WriteLine("from the Create method.")

                    DisplayProperties(createdCrypto)
                Else
                    Write("Unable to create CustomCrytpo from ")
                    WriteLine(" the Create method.")
                End If
            Catch ex As Exception
                WriteLine(ex.ToString())
            End Try

            ' Align interface and conclude application.
            WriteLine("This sample completed successfully;" + _
                " press Exit to continue.")

            ' Reset the cursor.
            tbxOutput.Cursor = Cursors.Default
        End Sub
        ' Display the properties of the specified CustomCrypto object to
        ' the output texbox.
        Public Sub DisplayProperties( _
            ByVal customCrypto As Contoso.vbCustomCrypto)

            Try
                ' Retrieve the class description for the customCrypto object.
                Dim classDescription As String = customCrypto.ToString()

                WriteLine(classDescription)
                WriteLine("KeyExchangeAlgorithm: " + _
                    customCrypto.KeyExchangeAlgorithm)
                WriteLine("SignatureAlgorithm: " + _
                    customCrypto.SignatureAlgorithm)
                WriteLine("KeySize: " + customCrypto.KeySize.ToString())
                WriteLine("Parameters described in Xml format:")
                WriteLine(customCrypto.ToXmlString(True))

                ' Display the MinSize, MaxSize, and SkipSize properties of 
                ' each KeySize item in the local keySizes member variable.
                Dim legalKeySizes() As KeySizes = customCrypto.LegalKeySizes
                If (legalKeySizes.Length > 0) Then
                    For i As Integer = 0 To legalKeySizes.Length - 1 Step 1
                        Write("Keysize" + i.ToString() + " min, max, step: ")
                        Write(legalKeySizes(i).MinSize.ToString() + ", ")
                        Write(legalKeySizes(i).MaxSize.ToString() + ", ")
                        Write(legalKeySizes(i).SkipSize.ToString() + ", ")
                        WriteLine("")
                    Next
                End If
            Catch ex As Exception
                WriteLine("Caught unexpected exception: " + ex.ToString())
            End Try
        End Sub
        ' Write the specified message and carriage return to the output
        ' textbox.
        Private Sub WriteLine(ByVal message As String)
            tbxOutput.AppendText(message + vbCrLf)
        End Sub
        ' Write the specified message to the output textbox.
        Private Sub Write(ByVal message As String)
            tbxOutput.AppendText(message)
        End Sub
        ' Event handler for Exit button.
        Private Sub Button2_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button2.Click

            Application.Exit()
        End Sub


        Public Sub New()
            MyBase.New()

            'This call is required by the Windows Form Designer.
            InitializeComponent()

            'Add any initialization after the InitializeComponent() call

        End Sub

        'Form overrides dispose to clean up the component list.
        Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
            If disposing Then
                If Not (components Is Nothing) Then
                    components.Dispose()
                End If
            End If
            MyBase.Dispose(disposing)
        End Sub

        'Required by the Windows Form Designer
        Private components As System.ComponentModel.IContainer

        'NOTE: The following procedure is required by the Windows Form 
        'Designer. It can be modified using the Windows Form Designer. 
        'Do not modify it using the code editor.
        Friend WithEvents Panel2 As System.Windows.Forms.Panel
        Friend WithEvents Panel1 As System.Windows.Forms.Panel
        Friend WithEvents Button1 As System.Windows.Forms.Button
        Friend WithEvents Button2 As System.Windows.Forms.Button
        Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox
        <System.Diagnostics.DebuggerStepThrough()> _
        Private Sub InitializeComponent()
            Me.Panel2 = New System.Windows.Forms.Panel
            Me.Button1 = New System.Windows.Forms.Button
            Me.Button2 = New System.Windows.Forms.Button
            Me.Panel1 = New System.Windows.Forms.Panel
            Me.tbxOutput = New System.Windows.Forms.RichTextBox
            Me.Panel2.SuspendLayout()
            Me.Panel1.SuspendLayout()
            Me.SuspendLayout()
            '
            'Panel2
            '
            Me.Panel2.Controls.Add(Me.Button1)
            Me.Panel2.Controls.Add(Me.Button2)
            Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom
            Me.Panel2.DockPadding.All = 20
            Me.Panel2.Location = New System.Drawing.Point(0, 320)
            Me.Panel2.Name = "Panel2"
            Me.Panel2.Size = New System.Drawing.Size(616, 64)
            Me.Panel2.TabIndex = 1
            '
            'Button1
            '
            Me.Button1.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button1.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button1.Location = New System.Drawing.Point(446, 20)
            Me.Button1.Name = "Button1"
            Me.Button1.Size = New System.Drawing.Size(75, 24)
            Me.Button1.TabIndex = 2
            Me.Button1.Text = "&Run"
            '
            'Button2
            '
            Me.Button2.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button2.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button2.Location = New System.Drawing.Point(521, 20)
            Me.Button2.Name = "Button2"
            Me.Button2.Size = New System.Drawing.Size(75, 24)
            Me.Button2.TabIndex = 3
            Me.Button2.Text = "E&xit"
            '
            'Panel1
            '
            Me.Panel1.Controls.Add(Me.tbxOutput)
            Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill
            Me.Panel1.DockPadding.All = 20
            Me.Panel1.Location = New System.Drawing.Point(0, 0)
            Me.Panel1.Name = "Panel1"
            Me.Panel1.Size = New System.Drawing.Size(616, 320)
            Me.Panel1.TabIndex = 2
            '
            'tbxOutput
            '
            Me.tbxOutput.AccessibleDescription = _
                "Displays output from application."
            Me.tbxOutput.AccessibleName = "Output textbox."
            Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill
            Me.tbxOutput.Location = New System.Drawing.Point(20, 20)
            Me.tbxOutput.Name = "tbxOutput"
            Me.tbxOutput.Size = New System.Drawing.Size(576, 280)
            Me.tbxOutput.TabIndex = 1
            Me.tbxOutput.Text = "Click the Run button to run the application."
            '
            'Form1
            '
            Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
            Me.ClientSize = New System.Drawing.Size(616, 384)
            Me.Controls.Add(Me.Panel1)
            Me.Controls.Add(Me.Panel2)
            Me.Name = "Form1"
            Me.Text = "AsymmetricAlgorithm"
            Me.Panel2.ResumeLayout(False)
            Me.Panel1.ResumeLayout(False)
            Me.ResumeLayout(False)

        End Sub

    End Class
End Namespace
'
' This sample produces the following output:
'
' *** CustomCrypto created with default parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 8
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' 
' *** CustomCrypto created with custom parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 64
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' Unable to create CustomCrytpo from  the Create method
' This sample completed successfully; press Enter to exit.

Tady je další třídy, která ukazuje, jak používat vlastní třídy.Here's an additional class that demonstrates how to use the custom class.

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

using namespace System;
using namespace System::Xml;
using namespace System::Text;
using namespace System::Security::Cryptography;

// Display the properties of the specified CustomCrypto object to the
// console.
static void DisplayProperties(Contoso::CustomCrypto^ customCryptoAlgorithm)
{
    // Retrieve the class description for the customCrypto object.
    String^ classDescription = customCryptoAlgorithm->ToString();

    Console::WriteLine(classDescription);
    Console::WriteLine("KeyExchangeAlgorithm: {0}",
        customCryptoAlgorithm->KeyExchangeAlgorithm);
    Console::WriteLine("SignatureAlgorithm: {0}",
        customCryptoAlgorithm->SignatureAlgorithm);
    Console::WriteLine("KeySize: {0}",
        customCryptoAlgorithm->KeySize);
    Console::WriteLine("Parameters described in Xml format:");
    Console::WriteLine(customCryptoAlgorithm->ToXmlString(true));

    // Display the MinSize, MaxSize, and SkipSize properties of
    // each KeySize item in the local keySizes member variable.
    array<KeySizes^>^ legalKeySizes = customCryptoAlgorithm->LegalKeySizes;
    for (int i = 0; i < legalKeySizes->Length; i++)
    {
        Console::WriteLine(
            "Keysize{0} min, max, step: {1}, {2}, {3}, ", i,
            legalKeySizes[i]->MinSize,
            legalKeySizes[i]->MaxSize,
            legalKeySizes[i]->SkipSize);
    }
}

[STAThread]
int main()
{
    // Construct a CustomCrypto object and initialize its
    // CspParameters.
    Contoso::CustomCrypto^ customCryptoAlgorithm = gcnew Contoso::CustomCrypto();
    customCryptoAlgorithm->InitializeParameters();

    // Display properties of the current customCrypto object.
    Console::WriteLine(
        "*** CustomCrypto created with default parameters:");
    DisplayProperties(customCryptoAlgorithm);

    // Release all the resources used by this instance of
    // CustomCrypto.
    customCryptoAlgorithm->Clear();

    customCryptoAlgorithm = gcnew Contoso::CustomCrypto(64);
    // Create new parameters and set them by using the FromXmlString
    // method.
    String^ parameterXml = "<CustomCryptoKeyValue>" +
        "<ProviderName>Contoso</ProviderName>" +
        "<KeyContainerName>SecurityBin2</KeyContainerName>" +
        "<KeyNumber>1</KeyNumber>" +
        "<ProviderType>2</ProviderType>" +
        "</CustomCryptoKeyValue>";
    customCryptoAlgorithm->FromXmlString(parameterXml);

    // Display the properties of a customCrypto object created with
    // custom parameters.
    Console::WriteLine(
        "{0}*** CustomCrypto created with custom parameters:", Environment::NewLine);
    DisplayProperties(customCryptoAlgorithm);

    // Create an object by using the assembly name.
    Contoso::CustomCrypto^ cryptoFromAssembly =
        Contoso::CustomCrypto::Create("CustomCrypto");
    if (cryptoFromAssembly != nullptr)
    {
        Console::WriteLine("{0}*** Successfully created " +
            "CustomCrypto from the Create method.", Environment::NewLine);
        DisplayProperties(cryptoFromAssembly);
    }
    else
    {
        Console::WriteLine("Unable to create CustomCrypto from " +
            "the Create method.");
    }

    Console::WriteLine(
        "This sample completed successfully; press Enter to exit.");
    Console::ReadLine();
}

//
// This sample produces the following output:
//
// *** CustomCrypto created with default parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 8
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8,
//
// *** CustomCrypto created with custom parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 64
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8,
// Unable to create CustomCrypto from the Create method
// This sample completed successfully; press Enter to exit.
    class CustomCryptoImpl
    {
        [STAThread]
        static void Main(string[] args)
        {
            // Construct a CustomCrypto object and initialize its
            // CspParameters.
            CustomCrypto customCrypto = new CustomCrypto();
            customCrypto.InitializeParameters();

            // Display properties of the current customCrypto object.
            Console.WriteLine("*** CustomCrypto created with default " + 
                "parameters:");
            DisplayProperties(customCrypto);

            // Release all the resources used by this instance of 
            // CustomCrytpo.
            customCrypto.Clear();

            customCrypto = new CustomCrypto(64);
            // Create new parameters and set them by using the FromXmlString
            // method.
            string parameterXml = "<CustomCryptoKeyValue>";
            parameterXml += "<ProviderName>Contoso</ProviderName>";
            parameterXml += "<KeyContainerName>SecurityBin2";
            parameterXml += "</KeyContainerName>";
            parameterXml += "<KeyNumber>1</KeyNumber>";
            parameterXml += "<ProviderType>2</ProviderType>";
            parameterXml += "</CustomCryptoKeyValue>";
            customCrypto.FromXmlString(parameterXml);

            // Display the properties of a customCrypto object created with
            // custom parameters.
            Console.WriteLine("\n*** " + 
                "CustomCrypto created with custom parameters:");
            DisplayProperties(customCrypto);

            // Create an object by using the assembly name.
            try
            {
                CustomCrypto myCryptoA = CustomCrypto.Create("CustomCrypto");
                if (myCryptoA != null)
                {
                    Console.Write("\n*** " + 
                        "Successfully created CustomCrytpo from");
                    Console.WriteLine(" the Create method.");

                    DisplayProperties(myCryptoA);
                }
                else
                {
                    Console.Write("Unable to create CustomCrytpo from ");
                    Console.WriteLine(" the Create method.");
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            
            Console.WriteLine("This sample completed successfully; " +
                "press Enter to exit.");
            Console.ReadLine();
        }
        // Display the properties of the specified CustomCrypto object to the
        // console.
        public static void DisplayProperties(CustomCrypto customCrypto)
        {
            try
            {
                // Retrieve the class description for the customCrypto object.
                string classDescription = customCrypto.ToString();

                Console.WriteLine(classDescription);
                Console.Write("KeyExchangeAlgorithm: ");
                Console.WriteLine(customCrypto.KeyExchangeAlgorithm);
                Console.Write("SignatureAlgorithm: ");
                Console.WriteLine(customCrypto.SignatureAlgorithm);
                Console.WriteLine("KeySize: " + customCrypto.KeySize);
                Console.WriteLine("Parameters described in Xml format:");
                Console.WriteLine(customCrypto.ToXmlString(true));

                // Display the MinSize, MaxSize, and SkipSize properties of 
                // each KeySize item in the local keySizes member variable.
                KeySizes[] legalKeySizes = customCrypto.LegalKeySizes;
                if (legalKeySizes.Length > 0)
                {
                    for (int i=0; i < legalKeySizes.Length; i++)
                    {
                        Console.Write("Keysize" + i + " min, max, step: ");
                        Console.Write(legalKeySizes[i].MinSize + ", ");
                        Console.Write(legalKeySizes[i].MaxSize + ", ");
                        Console.WriteLine(legalKeySizes[i].SkipSize + ", ");
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("Caught unexpected exception: " + 
                    ex.ToString());
            }
        }
    }
}
//
// This sample produces the following output:
//
// *** CustomCrypto created with default parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 8
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// 
// *** CustomCrypto created with custom parameters:
// Contoso.vbCustomCrypto
// KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
// SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
// KeySize: 64
// Parameters described in Xml format:
// <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
// <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
// <ProviderType>2</ProviderType></CustomCryptoKeyValue>
// Keysize0 min, max, step: 8, 64, 8, 
// Unable to create CustomCrytpo from  the Create method
// This sample completed successfully; press Exit to continue.
    Class Form1
        Inherits System.Windows.Forms.Form

        ' Event handler for Run button.
        Private Sub Button1_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button1.Click

            tbxOutput.Cursor = Cursors.WaitCursor
            tbxOutput.Text = ""

            ' Construct a CustomCrypto object and initialize its
            ' CspParameters.
            Dim customCrypto As New Contoso.vbCustomCrypto
            customCrypto.InitializeParameters()

            ' Display properties of the current vbCustomCrypto object.
            WriteLine("*** CustomCrypto created with default parameters:")
            DisplayProperties(customCrypto)

            ' Release all the resources used by this instance of CustomCrytpo.
            customCrypto.Clear()

            customCrypto = New Contoso.vbCustomCrypto(64)
            ' Create new parameters and set them by using the
            ' FromXmlString method.
            Dim parameterXml As String = "<CustomCryptoKeyValue>"
            parameterXml += "<ProviderName>Contoso</ProviderName>"
            parameterXml += "<KeyContainerName>SecurityBin2"
            parameterXml += "</KeyContainerName>"
            parameterXml += "<KeyNumber>1</KeyNumber>"
            parameterXml += "<ProviderType>2</ProviderType>"
            parameterXml += "</CustomCryptoKeyValue>"
            customCrypto.FromXmlString(parameterXml)

            ' Display the properties of a customCrypto object created with
            ' custom parameters.
            WriteLine(vbCrLf + "*** " + _
                "CustomCrypto created with custom parameters:")
            DisplayProperties(customCrypto)

            ' Create an object by using the assembly name.
            Try
                Dim createdCrypto As Contoso.vbCustomCrypto
                createdCrypto = customCrypto.Create("vbCustomCrypto")

                If (Not createdCrypto Is Nothing) Then
                    Write(vbCrLf + "*** Successfully created vbCustomCrytpo ")
                    WriteLine("from the Create method.")

                    DisplayProperties(createdCrypto)
                Else
                    Write("Unable to create CustomCrytpo from ")
                    WriteLine(" the Create method.")
                End If
            Catch ex As Exception
                WriteLine(ex.ToString())
            End Try

            ' Align interface and conclude application.
            WriteLine("This sample completed successfully;" + _
                " press Exit to continue.")

            ' Reset the cursor.
            tbxOutput.Cursor = Cursors.Default
        End Sub
        ' Display the properties of the specified CustomCrypto object to
        ' the output texbox.
        Public Sub DisplayProperties( _
            ByVal customCrypto As Contoso.vbCustomCrypto)

            Try
                ' Retrieve the class description for the customCrypto object.
                Dim classDescription As String = customCrypto.ToString()

                WriteLine(classDescription)
                WriteLine("KeyExchangeAlgorithm: " + _
                    customCrypto.KeyExchangeAlgorithm)
                WriteLine("SignatureAlgorithm: " + _
                    customCrypto.SignatureAlgorithm)
                WriteLine("KeySize: " + customCrypto.KeySize.ToString())
                WriteLine("Parameters described in Xml format:")
                WriteLine(customCrypto.ToXmlString(True))

                ' Display the MinSize, MaxSize, and SkipSize properties of 
                ' each KeySize item in the local keySizes member variable.
                Dim legalKeySizes() As KeySizes = customCrypto.LegalKeySizes
                If (legalKeySizes.Length > 0) Then
                    For i As Integer = 0 To legalKeySizes.Length - 1 Step 1
                        Write("Keysize" + i.ToString() + " min, max, step: ")
                        Write(legalKeySizes(i).MinSize.ToString() + ", ")
                        Write(legalKeySizes(i).MaxSize.ToString() + ", ")
                        Write(legalKeySizes(i).SkipSize.ToString() + ", ")
                        WriteLine("")
                    Next
                End If
            Catch ex As Exception
                WriteLine("Caught unexpected exception: " + ex.ToString())
            End Try
        End Sub
        ' Write the specified message and carriage return to the output
        ' textbox.
        Private Sub WriteLine(ByVal message As String)
            tbxOutput.AppendText(message + vbCrLf)
        End Sub
        ' Write the specified message to the output textbox.
        Private Sub Write(ByVal message As String)
            tbxOutput.AppendText(message)
        End Sub
        ' Event handler for Exit button.
        Private Sub Button2_Click( _
            ByVal sender As System.Object, _
            ByVal e As System.EventArgs) Handles Button2.Click

            Application.Exit()
        End Sub


        Public Sub New()
            MyBase.New()

            'This call is required by the Windows Form Designer.
            InitializeComponent()

            'Add any initialization after the InitializeComponent() call

        End Sub

        'Form overrides dispose to clean up the component list.
        Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
            If disposing Then
                If Not (components Is Nothing) Then
                    components.Dispose()
                End If
            End If
            MyBase.Dispose(disposing)
        End Sub

        'Required by the Windows Form Designer
        Private components As System.ComponentModel.IContainer

        'NOTE: The following procedure is required by the Windows Form 
        'Designer. It can be modified using the Windows Form Designer. 
        'Do not modify it using the code editor.
        Friend WithEvents Panel2 As System.Windows.Forms.Panel
        Friend WithEvents Panel1 As System.Windows.Forms.Panel
        Friend WithEvents Button1 As System.Windows.Forms.Button
        Friend WithEvents Button2 As System.Windows.Forms.Button
        Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox
        <System.Diagnostics.DebuggerStepThrough()> _
        Private Sub InitializeComponent()
            Me.Panel2 = New System.Windows.Forms.Panel
            Me.Button1 = New System.Windows.Forms.Button
            Me.Button2 = New System.Windows.Forms.Button
            Me.Panel1 = New System.Windows.Forms.Panel
            Me.tbxOutput = New System.Windows.Forms.RichTextBox
            Me.Panel2.SuspendLayout()
            Me.Panel1.SuspendLayout()
            Me.SuspendLayout()
            '
            'Panel2
            '
            Me.Panel2.Controls.Add(Me.Button1)
            Me.Panel2.Controls.Add(Me.Button2)
            Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom
            Me.Panel2.DockPadding.All = 20
            Me.Panel2.Location = New System.Drawing.Point(0, 320)
            Me.Panel2.Name = "Panel2"
            Me.Panel2.Size = New System.Drawing.Size(616, 64)
            Me.Panel2.TabIndex = 1
            '
            'Button1
            '
            Me.Button1.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button1.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button1.Location = New System.Drawing.Point(446, 20)
            Me.Button1.Name = "Button1"
            Me.Button1.Size = New System.Drawing.Size(75, 24)
            Me.Button1.TabIndex = 2
            Me.Button1.Text = "&Run"
            '
            'Button2
            '
            Me.Button2.Dock = System.Windows.Forms.DockStyle.Right
            Me.Button2.Font = New System.Drawing.Font( _
                "Microsoft Sans Serif", _
                9.0!, _
                System.Drawing.FontStyle.Regular, _
                System.Drawing.GraphicsUnit.Point, _
                CType(0, Byte))
            Me.Button2.Location = New System.Drawing.Point(521, 20)
            Me.Button2.Name = "Button2"
            Me.Button2.Size = New System.Drawing.Size(75, 24)
            Me.Button2.TabIndex = 3
            Me.Button2.Text = "E&xit"
            '
            'Panel1
            '
            Me.Panel1.Controls.Add(Me.tbxOutput)
            Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill
            Me.Panel1.DockPadding.All = 20
            Me.Panel1.Location = New System.Drawing.Point(0, 0)
            Me.Panel1.Name = "Panel1"
            Me.Panel1.Size = New System.Drawing.Size(616, 320)
            Me.Panel1.TabIndex = 2
            '
            'tbxOutput
            '
            Me.tbxOutput.AccessibleDescription = _
                "Displays output from application."
            Me.tbxOutput.AccessibleName = "Output textbox."
            Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill
            Me.tbxOutput.Location = New System.Drawing.Point(20, 20)
            Me.tbxOutput.Name = "tbxOutput"
            Me.tbxOutput.Size = New System.Drawing.Size(576, 280)
            Me.tbxOutput.TabIndex = 1
            Me.tbxOutput.Text = "Click the Run button to run the application."
            '
            'Form1
            '
            Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
            Me.ClientSize = New System.Drawing.Size(616, 384)
            Me.Controls.Add(Me.Panel1)
            Me.Controls.Add(Me.Panel2)
            Me.Name = "Form1"
            Me.Text = "AsymmetricAlgorithm"
            Me.Panel2.ResumeLayout(False)
            Me.Panel1.ResumeLayout(False)
            Me.ResumeLayout(False)

        End Sub

    End Class
End Namespace
'
' This sample produces the following output:
'
' *** CustomCrypto created with default parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 8
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin1</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' 
' *** CustomCrypto created with custom parameters:
' Contoso.vbCustomCrypto
' KeyExchangeAlgorithm: RSA-PKCS1-KeyEx
' SignatureAlgorithm: http://www.w3.org/2000/09/xmldsig#rsa-sha1
' KeySize: 64
' Parameters described in Xml format:
' <CustomCryptoKeyValue><KeyContainerName>SecurityBin2</KeyContainerName>
' <KeyNumber>1</KeyNumber><ProviderName>Contoso</ProviderName>
' <ProviderType>2</ProviderType></CustomCryptoKeyValue>
' Keysize0 min, max, step: 8, 64, 8, 
' Unable to create CustomCrytpo from  the Create method
' This sample completed successfully; press Enter to exit.

Poznámky

Asymetrické kryptografické algoritmy, neboli algoritmy veřejného klíče, vyžadují, aby odesílatel a příjemce udržovat pár klíče související: privátní klíč a veřejný klíč.Asymmetric cryptographic algorithms, also known as public-key algorithms, require that both sender and receiver maintain a pair of related keys: a private key and a public key. Oba klíče jsou jedinečné pro entitu.Both keys are unique to the entity. Veřejný klíč může být k dispozici všem uživatelům; Tento klíč se používá pro šifrování dat, které je odesláno příjemce.The public key can be made available to anyone; this key is used for encoding data that is sent to a receiver. Privátní klíč se musí zajistit soukromé příjemce; Tento klíč se používá pro dekódování zprávy kódovaný pomocí veřejného klíče příjemce.The private key must be kept private by the receiver; this key is used for decoding messages encoded using the receiver's public key. RSACryptoServiceProvider Třída je implementací algoritmu veřejného klíče.The RSACryptoServiceProvider class is an implementation of a public-key algorithm. Podrobné informace o šifrování s veřejným klíčem a algoritmy, naleznete v tématu v části "Šifrování s veřejným klíčem" šifrovacím službám.For an in-depth discussion of public-key encryption and algorithms, see the "Public-Key Encryption" section in Cryptographic Services. Informace o tom, jak používat nástroj Strong Name (Sn.exe) k vytvoření párů klíčů najdete v tématu jak: Vytvoření páru veřejného a privátního klíče.For information about how to use the Strong Name tool (Sn.exe) to create key pairs, see How to: Create a Public-Private Key Pair.

Systémy veřejných klíčů můžete použít k vytvoření digitální podpisy.You can use public-key systems to form digital signatures. Digitální podpisy se používají k lepší ochraně integritu dat.Digital signatures are used to help to protect the integrity of data. Například používat systém veřejný klíč k podepsání zprávy, odesílatel nejprve platí funkce hash pro zpráva, kterou chcete vytvořit hodnota hash.For example, to use a public-key system to digitally sign a message, the sender first applies a hash function to the message to create a message digest. Odesílatel pak zašifruje hodnotu hash pomocí soukromého klíče odesílatele k vytvoření podpisu osobní odesílatele.The sender then encrypts the message digest with the sender's private key to create the sender's personal signature. Při přijetí zprávy a podpis, příjemce dešifruje podpis pomocí veřejného klíče odesílatele obnovení hodnotu hash a hodnot hash zpráv pomocí stejné hashovacího algoritmu, který odesílatel používá.Upon receiving the message and signature, the receiver decrypts the signature using the sender's public key to recover the message digest and hashes the message using the same hash algorithm that the sender used. Pokud hodnota hash, která vypočítá příjemce odpovídá hodnota hash přijatých od odesílatele, příjemce, můžete předpokládat, že zpráva nebyla změněna při přenosu.If the message digest that the receiver computes matches the message digest received from the sender, the receiver can assume that the message was not altered while in transit. Protože veřejné klíče odesílatele je společné znalosti, mějte na paměti, že všem uživatelům ověřit podpis.Note that anyone can verify a signature, because the sender's public key is common knowledge. Tato technika nezachovává tajemství zprávy. pro zprávy být tajný se musí také být zašifrován.This technique does not retain the secrecy of the message; for the message to be secret, it must also be encrypted.

Rozhraní .NET Framework poskytuje následující třídy, které implementují algoritmy digitální podpis: DSACryptoServiceProvider, RSACryptoServiceProvider, ECDsa (základní třídy), a ECDsaCng.The .NET Framework provides the following classes that implement digital signature algorithms: DSACryptoServiceProvider, RSACryptoServiceProvider, ECDsa (base class), and ECDsaCng.

System.Security.Cryptography Obor názvů obsahuje konkrétní třídy pro RSA a DSA pouze.The System.Security.Cryptography namespace provides concrete classes for RSA and DSA only.

Zjistěte, jak použít algoritmus RSA k šifrování a dešifrování dat XML a vytvořit a ověřit XML – digitální podpisy, najdete v těchto článcích:To learn how to use the RSA algorithm to encrypt and decrypt XML data, and create and verify XML digital signatures, see these articles:

Konstruktory

AsymmetricAlgorithm() AsymmetricAlgorithm() AsymmetricAlgorithm() AsymmetricAlgorithm()

Inicializuje novou instanci třídy AsymmetricAlgorithm třídy.Initializes a new instance of the AsymmetricAlgorithm class.

Pole

KeySizeValue KeySizeValue KeySizeValue KeySizeValue

Představuje velikost v bitech, modulu klíče používané asymetrického algoritmu.Represents the size, in bits, of the key modulus used by the asymmetric algorithm.

LegalKeySizesValue LegalKeySizesValue LegalKeySizesValue LegalKeySizesValue

Určuje velikostí klíče, které jsou podporovány asymetrického algoritmu.Specifies the key sizes that are supported by the asymmetric algorithm.

Vlastnosti

KeyExchangeAlgorithm KeyExchangeAlgorithm KeyExchangeAlgorithm KeyExchangeAlgorithm

Při přepisu v odvozené třídě, získá název chcete algoritmus výměny klíčů.When overridden in a derived class, gets the name of the key exchange algorithm. V opačném případě vyvolá NotImplementedException.Otherwise, throws an NotImplementedException.

KeySize KeySize KeySize KeySize

Získá nebo nastaví velikost v bitech, modulu klíče používané asymetrického algoritmu.Gets or sets the size, in bits, of the key modulus used by the asymmetric algorithm.

LegalKeySizes LegalKeySizes LegalKeySizes LegalKeySizes

Získá velikostí klíče, které jsou podporovány asymetrického algoritmu.Gets the key sizes that are supported by the asymmetric algorithm.

SignatureAlgorithm SignatureAlgorithm SignatureAlgorithm SignatureAlgorithm

Při implementaci v odvozené třídě získá název podpisového algoritmu.When implemented in a derived class, gets the name of the signature algorithm. V opačném případě vždy vyvolá NotImplementedException.Otherwise, always throws a NotImplementedException.

Metody

Clear() Clear() Clear() Clear()

Uvolní všechny prostředky používané AsymmetricAlgorithm třídy.Releases all resources used by the AsymmetricAlgorithm class.

Create() Create() Create() Create()

Vytvoří výchozí kryptografických objekt použitý k provedení asymetrického algoritmu.Creates a default cryptographic object used to perform the asymmetric algorithm.

Create(String) Create(String) Create(String) Create(String)

Vytvoří instanci zadaného provádění asymetrického algoritmu.Creates an instance of the specified implementation of an asymmetric algorithm.

Dispose() Dispose() Dispose() Dispose()

Uvolní všechny prostředky používané aktuální instancí třídy AsymmetricAlgorithm třídy.Releases all resources used by the current instance of the AsymmetricAlgorithm class.

Dispose(Boolean) Dispose(Boolean) Dispose(Boolean) Dispose(Boolean)

Uvolní nespravované prostředky využívané třídou AsymmetricAlgorithm a volitelně také spravované prostředky.Releases the unmanaged resources used by the AsymmetricAlgorithm class and optionally releases the managed resources.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Určuje, zda se zadaný objekt rovná aktuálnímu objektu.Determines whether the specified object is equal to the current object.

(Inherited from Object)
ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters) ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters) ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters) ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters)
ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters) ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters) ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters) ExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters)
ExportPkcs8PrivateKey() ExportPkcs8PrivateKey() ExportPkcs8PrivateKey() ExportPkcs8PrivateKey()
ExportSubjectPublicKeyInfo() ExportSubjectPublicKeyInfo() ExportSubjectPublicKeyInfo() ExportSubjectPublicKeyInfo()
FromXmlString(String) FromXmlString(String) FromXmlString(String) FromXmlString(String)

Při přepisu v odvozené třídě, rekonstruuje AsymmetricAlgorithm objekt z řetězce XML.When overridden in a derived class, reconstructs an AsymmetricAlgorithm object from an XML string. V opačném případě vyvolá NotImplementedException.Otherwise, throws a NotImplementedException.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Slouží jako výchozí funkce hash.Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

Získá Type aktuální instance.Gets the Type of the current instance.

(Inherited from Object)
ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, ReadOnlySpan<Byte>, Int32) ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, ReadOnlySpan<Byte>, Int32) ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, ReadOnlySpan<Byte>, Int32) ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, ReadOnlySpan<Byte>, Int32)
ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, ReadOnlySpan<Byte>, Int32) ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, ReadOnlySpan<Byte>, Int32) ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, ReadOnlySpan<Byte>, Int32) ImportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, ReadOnlySpan<Byte>, Int32)
ImportPkcs8PrivateKey(ReadOnlySpan<Byte>, Int32) ImportPkcs8PrivateKey(ReadOnlySpan<Byte>, Int32) ImportPkcs8PrivateKey(ReadOnlySpan<Byte>, Int32) ImportPkcs8PrivateKey(ReadOnlySpan<Byte>, Int32)
ImportSubjectPublicKeyInfo(ReadOnlySpan<Byte>, Int32) ImportSubjectPublicKeyInfo(ReadOnlySpan<Byte>, Int32) ImportSubjectPublicKeyInfo(ReadOnlySpan<Byte>, Int32) ImportSubjectPublicKeyInfo(ReadOnlySpan<Byte>, Int32)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Vytvoří Mělkou kopii aktuální Object.Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

Vrací řetězec, který představuje aktuální objekt.Returns a string that represents the current object.

(Inherited from Object)
ToXmlString(Boolean) ToXmlString(Boolean) ToXmlString(Boolean) ToXmlString(Boolean)

Při přepisu v odvozené třídě vytvoří a vrátí reprezentaci XML řetězec aktuálního AsymmetricAlgorithm objektu.When overridden in a derived class, creates and returns an XML string representation of the current AsymmetricAlgorithm object. V opačném případě vyvolá NotImplementedException.Otherwise, throws a NotImplementedException.

TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters, Span<Byte>, Int32) TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters, Span<Byte>, Int32) TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters, Span<Byte>, Int32) TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Byte>, PbeParameters, Span<Byte>, Int32)
TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters, Span<Byte>, Int32) TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters, Span<Byte>, Int32) TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters, Span<Byte>, Int32) TryExportEncryptedPkcs8PrivateKey(ReadOnlySpan<Char>, PbeParameters, Span<Byte>, Int32)
TryExportPkcs8PrivateKey(Span<Byte>, Int32) TryExportPkcs8PrivateKey(Span<Byte>, Int32) TryExportPkcs8PrivateKey(Span<Byte>, Int32) TryExportPkcs8PrivateKey(Span<Byte>, Int32)
TryExportSubjectPublicKeyInfo(Span<Byte>, Int32) TryExportSubjectPublicKeyInfo(Span<Byte>, Int32) TryExportSubjectPublicKeyInfo(Span<Byte>, Int32) TryExportSubjectPublicKeyInfo(Span<Byte>, Int32)

Explicitní implementace rozhraní

IDisposable.Dispose() IDisposable.Dispose() IDisposable.Dispose() IDisposable.Dispose()

Popis tohoto členu viz Dispose().For a description of this member, see Dispose().

Platí pro

Viz také