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SymmetricAlgorithm::CreateEncryptor Method

Creates a symmetric encryptor object with the current Key property and initialization vector (IV).

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

virtual ICryptoTransform^ CreateEncryptor()

Return Value

Type: System.Security.Cryptography::ICryptoTransform
A symmetric encryptor object.

If the current Key property is nullptr, the GenerateKey method is called to create a new random Key. If the current IV property is nullptr, the GenerateIV method is called to create a new random IV.

Use the CreateDecryptor overload with the same signature to decrypt the result of this method.

The following example encrypts a string using the transform object returned from the CreateEncryptor method.

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

class EncryptorExample
     static void Main()
         TripleDESCryptoServiceProvider^ tdesCSP = gcnew TripleDESCryptoServiceProvider();

         String^ quote =
             "Things may come to those who wait, but only the " +
             "things left by those who hustle. -- Abraham Lincoln";
         array<Byte>^ encQuote = EncryptString(tdesCSP, quote);

         Console::WriteLine("Encrypted Quote:\n");

         Console::WriteLine("\nDecrypted Quote:\n");
         Console::WriteLine(DecryptBytes(tdesCSP, encQuote));

     static array<Byte>^ EncryptString(SymmetricAlgorithm^ symAlg, String^ inString)
         array<Byte>^ inBlock = UnicodeEncoding::Unicode->GetBytes(inString);
         ICryptoTransform^ xfrm = symAlg->CreateEncryptor();
         array<Byte>^ outBlock = xfrm->TransformFinalBlock(inBlock, 0, inBlock->Length);

         return outBlock;

     static String^ DecryptBytes(SymmetricAlgorithm^ symAlg, array<Byte>^ inBytes)
         ICryptoTransform^ xfrm = symAlg->CreateDecryptor();
         array<Byte>^ outBlock = xfrm->TransformFinalBlock(inBytes, 0, inBytes->Length);

         return UnicodeEncoding::Unicode->GetString(outBlock);

int main()

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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