Android Question Cipher / Decipher Long Text

Quandalle said:

1) FTP transfer allows you to send binary files. It is not necessary to encode in base64

2) To encrypt a very long file, it is possible to slice it and encrypt each slice

For example encryption of a file by 4KB slice :

B4X:

Sub CryptFile (path As String, infile As String, outfile As String)
    dim buffersize as int = 1024*4
    dim password = "mypassword"
    Dim c As B4XCipher
    Dim Ist As InputStream
    Dim ost As OutputStream
    Dim count As Int = 0
    ost = File.OpenOutput(path,outfile,False)
    Ist = File.OpenInput(path,infile)
    Dim buffer(buffersize) As Byte
    Do While count <> -1
        count = Ist.ReadBytes(buffer, 0, buffer.length)
        Dim outbuff () As Byte
        outbuff = c.Encrypt(buffer,password)
        ost.WriteBytes(outbuff,0,outbuff.Length)
        Log(outbuff.Length)
    Loop
    Ist.Close
    ost.close
End Sub

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