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RSACryptoServiceProvider Constructor (Int32, CspParameters)

Initializes a new instance of the RSACryptoServiceProvider class with the specified key size and parameters.

Namespace:  System.Security.Cryptography
Assembly:  mscorlib (in mscorlib.dll)

public function RSACryptoServiceProvider(
	dwKeySize : int, 
	parameters : CspParameters


Type: System.Int32

The size of the key to use in bits.

Type: System.Security.Cryptography.CspParameters

The parameters to be passed to the cryptographic service provider (CSP).


The CSP cannot be acquired.


The key cannot be created.

This constructor creates or reuses a key container specified using the KeyContainerName field of the parameters parameter.

By default, this constructor creates an Exchange key pair suitable to encrypt session keys so that they can be safely stored and exchanged with other users. The generated key corresponds to a key generated using the AT_KEYEXCHANGE value used in the unmanaged Microsoft Cryptographic API (CAPI).

You can create a Signature key pair suitable for authenticating (digitally signed) messages or files by setting the KeyNumber field of the parameters parameter to the Signature value. This type of key corresponds to the AT_SIGNATURE value used in CAPI.

If you create an RSACryptoServiceProvider object with the Exchange value specified and then create another RSACryptoServiceProvider object with the Signature value specified, both keys will be placed in a single container if both objects specify the same key container name.

To create a key that is compatible with stong-name signing using the RSACryptoServiceProvider class, you must create a Signature key pair.

The following code example creates a RSACryptoServiceProvider, generates a new key, and stores it in a key container.

No code example is currently available or this language may not be supported.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0