XEncryption SetCryptMethods Function. Sets the crypt methods for encryption levels of type 4 or above. ABCpdf .NET PDF Library.

Sets the crypt methods for encryption levels of type 4 or above.

[C#]
void SetCryptMethods(CryptMethodType method)
void SetCryptMethods(CryptMethodType stringMethod, CryptMethodType streamMethod)

[Visual Basic]
Sub SetCryptMethods(method As CryptMethodType)
Sub SetCryptMethods(stringMethod As CryptMethodType, streamMethod As CryptMethodType)

may throw Exception()

The default crypt method for Type 4 is V2, which uses RC4 algorithm. Crypt method settings are in effect only when Type is 4 or above.

The CryptMethodType enumeration can take any of the following values:

• None – (Not supported.) An exception is thrown when it is used.
• Identity – No encryption.
• V2 – Uses the RC4 algorithm.
• AESV2 – Uses the AES algorithm with 128-bit encryption keys.
• AESV3 – Uses the AES algorithm with 256-bit encryption keys.

Because Adobe Reader does not support using more than one crypt methods per document (i.e. stringMethod≠streamMethod), an exception is thrown if you try to use multiple crypt methods. However, Identity is degenerate and can be used with other crypt methods.

Here we use 128-bit AES encryption.

[C#]
Doc theDoc = new Doc();
theDoc.FontSize = 96;
theDoc.AddText("Hello World!");
theDoc.Encryption.Type = 4;
theDoc.Encryption.SetCryptMethods(CryptMethodType.AESV2);
theDoc.Save(Server.MapPath("docencrypt.pdf"));
[Visual Basic]
Dim theDoc As New Doc()
theDoc.FontSize = 96
theDoc.AddText("Hello World!")
theDoc.Encryption.Type = 4
theDoc.Encryption.SetCryptMethods(CryptMethodType.AESV2)
theDoc.Save(Server.MapPath("docencrypt.pdf"))