How to extract OLE objects from Excel table using Python?

Question

I would like to use Python to extract OLE-objects from an Excel table into the Windows clipboard.

This post didn't help further since it is for VBA. And this post is still unanswered.

Assuming the given Excel table (with ChemDraw or ChemSketch OLE objects):

There are some Python modules which can handle Excel files, e.g. openpyxl, xlrd. The module win32clipboard can put data into the clipboard.

My Problems:

1. I don't see how to get the embedded OLE object to the clipboard. Probably, openpyxl and xlrd together with win32clipboard are not suited for this?
2. There is a Python module oletools which maybe can do it but I don't understand how it works. https://pypi.org/project/oletools/

From this page:

oleobj: to extract embedded objects from OLE files.

This seems to be exactly what I am looking for, however, I couldn't find any MCVEs. And unfortunately, the documentation of oleobj is basically reduced to: "read the source code and find out yourself". I would be grateful for hints and assistance.

My code so far:

### trying to extract OLE objects from Excel table into clipboard
from openpyxl import load_workbook
import win32clipboard as clpbd

def set_clipboard(data):
    clpbd.OpenClipboard()
    clpbd.EmptyClipboard()
    clpbd.SetClipboardText(data)    # I'm aware, this is only for text, is there anything for OLEs?
    clpbd.CloseClipboard()

def print_clipboard():
    clpbd.OpenClipboard()
    data = clpbd.GetClipboardData()
    clpbd.CloseClipboard()
    print(data)

wb = load_workbook(filename = 'tbChemOLE.xlsx')
ws = wb.active

myName = ws['A3'].value    # result: napthalene
myImage = ws['B3'].value   # result: None
myObject = ws['C3'].value  # result: None

set_clipboard(myName)
print_clipboard()          # result: Naphtalene
# set_clipboard(myImage)   # crash, because myImage is None
print_clipboard()     
# set_clipboard(myObject)  # crash, because myObject is None
print_clipboard()        

wb.close()
### end of code

Answer 1

I built a python module to do exactly this check it out over here. https://pypi.org/project/AttachmentsExtractor/ also the module can be run on any os.

after installing the library use the following code snippet:

 from AttachmentsExtractor import extractor
            
 abs_path_to_file='Please provide absolute path here '
 path_to_destination_directory = 'Please provide path of the directory where the extracted attachments should be stored'
 extractor.extract(abs_path_to_file,path_to_destination_directory) # returns true if one or more attachments are found else returns false.

Answer 2

In the meantime I found this post, where the OP actually didn't want the OLE objects on the clipboard, but for me it is fine. Actually, no need for openpyxl or xlrd, but win32com.client is required.

I can get all OLE objects, however, they are indexed (probably) in the sequence of their addition. So I need to create a dictionary with the row index as key and a set of OLE object index of and name as value.

Code:

### copy OLE object in certain cell to clipboard
import win32com.client as win32
import win32clipboard

excel = win32.gencache.EnsureDispatch('Excel.Application')
ffname = r'C:\Test\tbChemOLE.xlsx'
wb = excel.Workbooks.Open(ffname)
ws = wb.Worksheets.Item(1)
objs = ws.OLEObjects()

def get_all_OLEs():
    oleNo_dict = {}     # dictionary for all OLE objects
    for i in range(1,len(objs)+1):    # loop all OLE objects
        obj = objs.Item(i) 
        myRow = obj.TopLeftCell.Row        # row of OLE object
        myName = ws.Cells(myRow,1).Value   # corresponding name
        oleNo_dict[myRow] = (i, myName)
    return oleNo_dict

def get_OLE(row):
    try: 
        objs[oleNo_dict[row][0]].Copy()
        win32clipboard.OpenClipboard()
        data = win32clipboard.GetClipboardData(0xC004) # Binary access
        win32clipboard.CloseClipboard()
    except Exception as e:
        print(e)
        win32clipboard.OpenClipboard()
        win32clipboard.EmptyClipboard()
        win32clipboard.CloseClipboard()
    return oleNo_dict[row]
    # and OLE is on clipboard if found

oleNo_dict = get_all_OLEs()

row = 4
myMolecule = get_OLE(row)
print(myMolecule[1], "OLE object is now on the clipboard.")

wb.Close()
excel.Application.Quit()
### end of code

Result:

Anthracene OLE object is now on the clipboard.