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DataProtectionScope Enumeration

Specifies the scope of the data protection to be applied by the Protect method.

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

public enum DataProtectionScope

Member nameDescription
CurrentUserThe protected data is associated with the current user. Only threads running under the current user context can unprotect the data.
LocalMachineThe protected data is associated with the machine context. Any process running on the computer can unprotect data. This enumeration value is usually used in server-specific applications that run on a server where untrusted users are not allowed access.

This enumeration is used with the Protect and Unprotect methods to protect data through encryption.

Caution   The LocalMachine enumeration value allows multiple accounts to unprotect data. Use this value only when you trust every account on a computer. For most situations, you should use the CurrentUser value.

The following code example shows how to use data protection.

using System;
using System.Security.Cryptography;

public class DataProtectionSample
{
// Create byte array for additional entropy when using Protect method. 
	static byte [] s_aditionalEntropy = { 9, 8, 7, 6, 5 };

	public static void Main()
	{
// Create a simple byte array containing data to be encrypted.
		
byte [] secret = { 0, 1, 2, 3, 4, 1, 2, 3, 4 };

//Encrypt the data.
		byte [] encryptedSecret = Protect( secret );
		Console.WriteLine("The encrypted byte array is:");
		PrintValues(encryptedSecret);
		
// Decrypt the data and store in a byte array.
		byte [] originalData = Unprotect( encryptedSecret );
		Console.WriteLine("{0}The original data is:", Environment.NewLine);
		PrintValues(originalData);

	}

	public static byte [] Protect( byte [] data )
	{
		try
		{
			// Encrypt the data using DataProtectionScope.CurrentUser. The result can be decrypted 
			//  only by the same current user. 
			return ProtectedData.Protect( data, s_aditionalEntropy, DataProtectionScope.CurrentUser );
		} 
		catch (CryptographicException e)
		{
			Console.WriteLine("Data was not encrypted. An error occurred.");
			Console.WriteLine(e.ToString());
			return null;
		}
	}

	public static byte [] Unprotect( byte [] data )
	{
		try
		{
			//Decrypt the data using DataProtectionScope.CurrentUser. 
			return ProtectedData.Unprotect( data, s_aditionalEntropy, DataProtectionScope.CurrentUser );
		} 
		catch (CryptographicException e)
		{
			Console.WriteLine("Data was not decrypted. An error occurred.");
			Console.WriteLine(e.ToString());
			return null;
		}
	}

	public static void PrintValues( Byte[] myArr )  
	{
	      foreach ( Byte i in myArr )  
		  	{
		         Console.Write( "\t{0}", i );
			 }
      Console.WriteLine();
	 }

}

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

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
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