Excuse me each expert, VB.NET how to transfer cost interface data byte (), and then return from byte () interface of cost data,

Dim buffer As Byte ()=Nothing
Dim picStream1 As cost
Dim picStream As cost
PicStream=AxFoxitReaderSDK1. SaveToStream
'buffer=? '//cost interface data byte ()
'picStream1=? '//byte () back cost data interface
AxFoxitReaderSDK1. OpenStream (picStream1, "")