Encrypting information with RandomAccessFile library

[Erel]

RandomAccessFile v1.30 introduces two new methods named: WriteEncryptedObject and ReadEncryptedObject.
These methods are similar to WriteObject and ReadObject methods. The difference is that the new methods encrypt the object before writing it to a file and decrypt it before reading. The encryption algorithm is AES-256 which is considered to provide strong protection.

Android SQLite implementation doesn't support encryption. In many cases you can use these two methods instead. You can create a large Map or List with your own structures and save them to a file.
Edit: Using the new SQLCipher library you can encrypt SQLite databases: http://www.basic4ppc.com/forum/basic...r-library.html

Developers who are not familiar with WriteObject / ReadObject should try these methods. They are very easy to use and allow you to store complicated objects in a single line of code. Unlike File.WriteMap / WriteList which convert the data to a string, WriteObject and WriteEncryptedObject can write many types of data without losing any information.

You can see more information about the supported types here: Basic4android - RandomAccessFile

Example of writing an encrypted List to a file:

Sub Activity_Create(FirstTime As Boolean)
    Dim list1 As List
    list1.Initialize
    For i = 1 To 1000
        list1.Add("Item #" & i)
    Next
    'writing the object
    Dim raf As RandomAccessFile
    raf.Initialize(File.DirRootExternal, "1.dat", False)
    raf.WriteEncryptedObject(list1, "some secret password", raf.CurrentPosition)
    'you can continue to write more objects to this file
    '...
    raf.Close
    
    'reading the object
    Dim raf As RandomAccessFile
    raf.Initialize(File.DirRootExternal, "1.dat", False)
    Dim list2 As List
    list2 = raf.ReadEncryptedObject("some secret password", raf.CurrentPosition)
    Log(list2)
    raf.Close
End Sub

Other more advanced encryption methods are available in the encryption library: http://www.basic4ppc.com/forum/addit...n-library.html

The library is available here: http://www.basic4ppc.com/forum/addit...redobject.html

[AscySoft]

Right now I am working on exporting to some text files...

I use encryption method describe by you, above using WriteEncryptedObject.

The text files are OK, but the question is..
How do I decrypt them on Windows PC? (There I use net framework 2.0 application)
Could you enlighten me? Thanks, I know is not B4A, but is related anyway

[Erel]

You will not be able to use a file written with WriteEncryptedObject on the PC. You will need to encrypt the data yourself with the Encryption library.

[AscySoft]

Originally Posted by Erel

You will not be able to use a file written with WriteEncryptedObject on the PC. You will need to encrypt the data yourself with the Encryption library.

Thanks, I'm working on that.