Is it possible to write out the binary data of the #<variant 8204 ...> variant to a txt file?

[ekko]

I know that I can write the binary data of a .exe file into a txt file. My question is, can the binary data of the #<variant 8204 ...> variant also be written into a txt file?

[pkenewell]

@ekko It's very hard to determine what you want without any specific intention or code. But off the top of my head: have you looked into (vlax-variant-value)?

https://help.autodesk.com/view/ACD/2025/ENU/index.html?guid=GUID-D26E25ED-6D9A-4E0F-B7C3-CC10F95246F9

[ekko]

1 hour ago, pkenewell said:

@ekko It's very hard to determine what you want without any specific intention or code. But off the top of my head: have you looked into (vlax-variant-value)?

https://help.autodesk.com/view/ACD/2025/ENU/index.html?guid=GUID-D26E25ED-6D9A-4E0F-B7C3-CC10F95246F9

;;-----------------=={ Read Binary Stream }==-----------------;;
;;                                                            ;;
;;  Uses the ADO Stream Object to read a supplied file and    ;;
;;  returns a variant of bytes.                               ;;
;;------------------------------------------------------------;;
;;  Author: Lee Mac, Copyright © 2011 - www.lee-mac.com       ;;
;;------------------------------------------------------------;;
;;  Arguments:                                                ;;
;;  filename - filename of file to read.                      ;;
;;  len      - number of bytes to read                        ;;
;;  (if non-numerical, less than 1, or greater than the size  ;;
;;   of the file, everything is returned).                    ;;
;;------------------------------------------------------------;;
;;  Returns:                                                  ;;
;;  Variant of Binary data which may be converted to a list   ;;
;;  bytes using the relevant VL Variant functions or used     ;;
;;  with LM:WriteBinaryStream.                                ;;
;;------------------------------------------------------------;;

(defun LM:ReadBinaryStream ( filename len / ADOStream result ) (vl-load-com)
 
 (setq result
   (vl-catch-all-apply
     (function
       (lambda ( / size )
         (setq ADOStream (vlax-create-object "ADODB.Stream"))
         (vlax-invoke ADOStream 'Open)
         (vlax-put-property   ADOStream 'type 1)
         (vlax-invoke-method  ADOStream 'loadfromfile filename)
         (vlax-put-property   ADOStream 'position 0)
         (setq size (vlax-get ADOStream 'size))
         (vlax-invoke-method  ADOStream 'read (if (and (numberp len) (< 0 len size)) (fix len) -1))
       )
     )
   )
 )
 (if ADOStream (vlax-release-object ADOStream))

 (if (not (vl-catch-all-error-p result))
   result
 )
)
;;-----------------=={ Write Binary Stream }==----------------;;
;;                                                            ;;
;;  Uses the ADO Stream Object to write a variant of bytes to ;;
;;  a specified file. File is created if non-existent or      ;;
;;  overwritten if found.                                     ;;
;;------------------------------------------------------------;;
;;  Author: Lee Mac, Copyright © 2011 - www.lee-mac.com       ;;
;;------------------------------------------------------------;;
;;  Arguments:                                                ;;
;;  filename - filename of file to read.                      ;;
;;  data     - variant of binary data to write to the file.   ;;
;;             (as returned by LM:ReadBinaryStream)           ;;
;;------------------------------------------------------------;;
;;  Returns:  Filename of specified file, else nil.           ;;
;;------------------------------------------------------------;;

(defun LM:WriteBinaryStream ( filename data / ADOStream result ) (vl-load-com)
 
 (setq result
   (vl-catch-all-apply
     (function
       (lambda ( )
         (setq ADOStream (vlax-create-object "ADODB.Stream"))
         (vlax-put-property ADOStream 'type 1)
         (vlax-invoke ADOStream 'open)
         (vlax-invoke-method ADOStream 'write data)
         (vlax-invoke ADOStream 'savetofile filename 2)
       )
     )
   )
 )
 (if ADOStream (vlax-release-object ADOStream))

 (if (not (vl-catch-all-error-p result))
   file
 )
)

Like this function  LM:WriteBinaryStream ，But filename is a file, and I want to read the binary data of the variant.

[BIGAL]

Not sure what the end goal is and why, but did at some stage do a get and put of bytes. I may be wrong but is not a binary file made up of hex for each byte ?

 

Look into DEBUG.exe.

 

 

[GLAVCVS]

Hi
First of all, thank you LM for sharing this elegant and efficient code.
I have used the read function before. However, the write function is difficult for me: I can't get the 'data' argument to be formatted properly.

Has anyone managed to write anything that hasn't been read to another file with LM:ReadBinary...?

Any examples?

Thanks in advance

[GLAVCVS]

Ok
I solved it.
The problem was in the difference between 'vlax-invoke' and 'vlax-invoke-method'