iOS - Convertire un immagine in Base64

Ciao a tutti,
come si pu convertire una foto iOSImage in base64?
Riesco tranquillamente a fare il contrario, oppure a prelevare la foto da un campo blob del database ma non ho trovato alcun modo per la procedura inversa.

Ho visto qualche messaggio sul forum e altrove ma si parla solo della versione desktop.

[code]Public Function EncodeBase64_fromData(tmb As xojo.Core.MemoryBlock) as Text
'From Phillip Zedalis

Declare Function dataWithBytes Lib “UIKit” Selector “dataWithBytes:length:” (class_id As Ptr, bytes As Ptr, length As UInt32) As Ptr
Declare Function base64EncodedStringWithOptions Lib “UIKit” Selector “base64EncodedStringWithOptions:” (class_id As Ptr, options As UInt32) As CFStringRef
declare function NSClassFromString lib “Foundation.Framework” (clsName as CFStringRef) as ptr

// Create NSData pointer to be point of reference.
Dim data As Ptr
data = NSClassFromString(“NSData”)

// Create NSData object using xojo.Core.MemoryBlock
Dim dataRef as Ptr = dataWithBytes(data, tmb.Data, tmb.Size)

// Create Text object to hold Base64 encoded string.
Dim x As Text
x = base64EncodedStringWithOptions(dataRef, 0)

// Return Base64 encoded string
Return x

End Function
[/code]

Dim base64Text As Text = EncodeBase64_fromData(iOSImage1.ToData)

Thank you Jeremie.