ProtectedData.Protect Method
Assembly: System.Security (in system.security.dll)
'Declaration Public Shared Function Protect ( _ userData As Byte(), _ optionalEntropy As Byte(), _ scope As DataProtectionScope _ ) As Byte() 'Usage Dim userData As Byte() Dim optionalEntropy As Byte() Dim scope As DataProtectionScope Dim returnValue As Byte() returnValue = ProtectedData.Protect(userData, optionalEntropy, scope)
public static byte[] Protect ( byte[] userData, byte[] optionalEntropy, DataProtectionScope scope )
public static function Protect ( userData : byte[], optionalEntropy : byte[], scope : DataProtectionScope ) : byte[]
Parameters
- userData
A byte array containing data to protect.
- optionalEntropy
An additional byte array used to encrypt the data.
- scope
One of the DataProtectionScope values.
Return Value
A byte array representing the encrypted data.| Exception type | Condition |
|---|---|
| The userData parameter is a null reference (Nothing in Visual Basic). | |
| The cryptographic protection failed. | |
| The operating system does not support this method. This method can be used only with Microsoft Windows 2000 or later operating systems. | |
| The system ran out of memory while encrypting the data. |
This method can be used to protect data such as passwords, keys, or connection strings. The optionalEntropy parameter enables you to use additional information to protect the data. This information must also be used when unprotecting the data using the Unprotect method.
The following code example shows how to use data protection.
import System.*;
import System.Security.Cryptography.*;
public class DataProtectionSample
{
// Create byte array for additional entropy when using Protect method.
private static ubyte sAditionalEntropy[] = { 9, 8, 7, 6, 5 };
public static void main(String args[])
{
// Create a simple byte array containing data to be encrypted.
ubyte secret[] = { 0, 1, 2, 3, 4, 1, 2, 3, 4 };
//Encrypt the data.
ubyte encryptedSecret[] = Protect(secret);
Console.WriteLine("The encrypted byte array is:");
PrintValues(encryptedSecret);
// Decrypt the data and store in a byte array.
ubyte originalData[] = Unprotect(encryptedSecret);
Console.WriteLine("{0}The original data is:",
Environment.get_NewLine());
PrintValues(originalData);
} //main
public static ubyte[] Protect(ubyte data[])
{
try {
// Encrypt the data using DataProtectionScope.CurrentUser.
// The result can be decrypted only by the same current user.
return ProtectedData.Protect(data, sAditionalEntropy,
DataProtectionScope.CurrentUser);
}
catch (CryptographicException e) {
Console.WriteLine("Data was not encrypted. An error occurred.");
Console.WriteLine(e.ToString());
return null;
}
} //Protect
public static ubyte[] Unprotect(ubyte data[])
{
try {
//Decrypt the data using DataProtectionScope.CurrentUser.
return ProtectedData.Unprotect(data, sAditionalEntropy,
DataProtectionScope.CurrentUser);
}
catch (CryptographicException e) {
Console.WriteLine("Data was not decrypted. An error occurred.");
Console.WriteLine(e.ToString());
return null;
}
} //Unprotect
public static void PrintValues(ubyte myArr[])
{
for (int iCtr = 0; iCtr < myArr.length; iCtr++) {
ubyte i = myArr[iCtr];
Console.Write("\t{0}", System.Convert.ToString(i));
}
Console.WriteLine();
} //PrintValues
} //DataProtectionSample
- DataProtectionPermission with the associated ProtectData flag for permission to protect data.
Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.