How to convert a database blob field to a System.byte[] arra

Posted by hendersons on 22-Mar-2010 05:31

Hi,

I am storing a file in a blob field. I need to pass this to a .NET control as a parameter of type System.Byte[]. Is there any way to convert the blob field to a System.Byte[] type? 

One way would be to write the file temporarily to disk and them use the .NET System.IO.BinaryReader class to read it back in again.

Is there anyway to do this without writing the file to disk?

Thanks

OpenEdge Development - Forum

All Replies

Posted by hendersons on 23-Mar-2010 09:46

Hi,

I got this sorted using a System.IO.MemoryStream.

DEFINE VARIABLE m1         AS MEMPTR                 NO-UNDO. 
DEFINE VARIABLE iSize      AS INT                    NO-UNDO.
DEF    VAR      oMemStream AS System.IO.MemoryStream NO-UNDO.
DEF    VAR      ix         AS INT                    NO-UNDO.
          
 DEF TEMP-TABLE ttStore NO-UNDO
        FIELD ttData AS BLOB.
CREATE ttStore.
COPY-LOB FILE "file" TO ttStore.ttData NO-CONVERT .
 COPY-LOB ttStore.ttData TO m1 NO-CONVERT.
  iSize = GET-SIZE(m1).
          
 oMemStream = NEW System.IO.MemoryStream(iSize).
  DO ix = 1 TO iSize:
      oMemStream:WriteByte(GET-BYTE(m1,ix)).
  END.    
  SET-SIZE(m1) = 0.
  oMemStream:GetBuffer().
  oMemStream = ?.   

The  oMemStream:GetBuffer() will return the System.Byte[].


This thread is closed