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: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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