ProtectedMemory Class


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Provides methods for protecting and unprotecting memory. This class cannot be inherited.

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


[HostProtectionAttribute(SecurityAction::LinkDemand, MayLeakOnAbort = true)]
public ref class ProtectedMemory abstract sealed 

System_CAPS_pubmethodSystem_CAPS_staticProtect(array<Byte>^, MemoryProtectionScope)

Protects the specified data.

System_CAPS_pubmethodSystem_CAPS_staticUnprotect(array<Byte>^, MemoryProtectionScope)

Unprotects data in memory that was protected using the Protect method.

This class provides access to the Data Protection API (DPAPI) available in the Windows XP and later operating systems. This is a service that is provided by the operating system and does not require additional libraries. It provides encryption for sensitive data in memory.

The class consists of two wrappers for the unmanaged DPAPI, Protect and Unprotect. These two methods can be used to encrypt and decrypt data in memory.

The following example shows how to use data protection.

#using <System.Security.dll>

using namespace System;
using namespace System::Security::Cryptography;

int main()

   // Create the original data to be encrypted (The data length should be a multiple of 16).
   array<Byte>^secret = {1,2,3,4,1,2,3,4,1,2,3,4,1,2,3,4};

   // Encrypt the data in memory. The result is stored in the same same array as the original data.
   ProtectedMemory::Protect( secret, MemoryProtectionScope::SameLogon );

   // Decrypt the data in memory and store in the original array.
   ProtectedMemory::Unprotect( secret, MemoryProtectionScope::SameLogon );

.NET Framework
Available since 2.0

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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