RSACryptoServiceProvider.PersistKeyInCsp Property

Definition

Gets or sets a value indicating whether the key should be persisted in the cryptographic service provider (CSP).

C#
public bool PersistKeyInCsp { get; set; }

Property Value

true if the key should be persisted in the CSP; otherwise, false.

Examples

The following code example creates an RSACryptoServiceProvider object and persists the key to a key container.

C#
using System;
using System.Security.Cryptography;

class RSACSPSample
{

    static void Main()
    {

        string KeyContainerName = "MyKeyContainer";

        //Create a new key and persist it in
        //the key container.
        RSAPersistKeyInCSP(KeyContainerName);

        //Delete the key from the key container.
        RSADeleteKeyInCSP(KeyContainerName);
    }

    public static void RSAPersistKeyInCSP(string ContainerName)
    {
        try
        {
            // Create a new instance of CspParameters.  Pass
            // 13 to specify a DSA container or 1 to specify
            // an RSA container.  The default is 1.
            CspParameters cspParams = new CspParameters();

            // Specify the container name using the passed variable.
            cspParams.KeyContainerName = ContainerName;

            //Create a new instance of RSACryptoServiceProvider to generate
            //a new key pair.  Pass the CspParameters class to persist the
            //key in the container.  The PersistKeyInCsp property is true by
            //default, allowing the key to be persisted.
            RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider(cspParams);

            //Indicate that the key was persisted.
            Console.WriteLine("The RSA key was persisted in the container, \"{0}\".", ContainerName);
        }
        catch(CryptographicException e)
        {
            Console.WriteLine(e.Message);
        }
    }

    public static void RSADeleteKeyInCSP(string ContainerName)
    {
        try
        {
            // Create a new instance of CspParameters.  Pass
            // 13 to specify a DSA container or 1 to specify
            // an RSA container.  The default is 1.
            CspParameters cspParams = new CspParameters();

            // Specify the container name using the passed variable.
            cspParams.KeyContainerName = ContainerName;

            //Create a new instance of RSACryptoServiceProvider.
            //Pass the CspParameters class to use the
            //key in the container.
            RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider(cspParams);

            //Explicitly set the PersistKeyInCsp property to false
            //to delete the key entry in the container.
            RSAalg.PersistKeyInCsp = false;

            //Call Clear to release resources and delete the key from the container.
            RSAalg.Clear();

            //Indicate that the key was persisted.
            Console.WriteLine("The RSA key was deleted from the container, \"{0}\".", ContainerName);
        }
        catch(CryptographicException e)
        {
            Console.WriteLine(e.Message);
        }
    }
}

Remarks

Use this property to persist a key in a key container.

The PersistKeyInCsp property is automatically set to true when you specify a key container name in the KeyContainerName field of a CspParameters object and use it to initialize an RSACryptoServiceProvider object by calling one of the constructors with a parameters parameter.

The PersistKeyInCsp property has no effect if the RSACryptoServiceProvider object is created with a null key container name.

Applies to

Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

See also