Managing OLE Objects
Introduction
OLE (Object Linking and Embedding) is Microsoft’s framework for a compound document technology. Briefly, a compound document is something like a display desktop that can contain visual and information objects of all kinds: text, calendars, animations, sound, motion video, 3D, continually updated news, controls, and so forth. Each desktop object is an independent program entity that can interact with a user and also communicate with other objects on the desktop.
OLE (Object Linking and Embedding) is supported by many different programs and is used to make content created in one program available in another. For example, you can insert a Microsoft Word document into Microsoft Excel. To see what types of content you can insert, click Object on the Insert menu. Only programs that are installed on the computer and that support OLE objects appear in the Object type box.
Inserting OLE Objects into the Worksheet
Aspose.Cells for Python via .NET supports adding, extracting and manipulating OLE objects in worksheets. For this reason, Aspose.Cells for Python via .NET has the OleObjectCollection class, used to add a new OLE Object to the collection list. Another class, OleObject, represents an OLE Object. It has some important members:
- The image_data property specifies the image (icon) data of byte array type. The image will be displayed to show the OLE Object in the worksheet.
- The object_data property specifies the object data in the form of a byte array. This data will be shown in its related program when you double-click on the OLE Object icon.
The following example shows how to add an OLE Object(s) into a worksheet.
| from aspose.cells import Workbook | |
| from os import os, path | |
| import bytearray | |
| # For complete examples and data files, please go to https:# github.com/aspose-cells/Aspose.Cells-for-.NET | |
| # The path to the documents directory. | |
| dataDir = RunExamples.GetDataDir(".") | |
| # Create directory if it is not already present. | |
| IsExists = path.isdir(dataDir) | |
| if notIsExists: | |
| os.makedirs(dataDir) | |
| # Instantiate a new Workbook. | |
| workbook = Workbook() | |
| # Get the first worksheet. | |
| sheet = workbook.worksheets[0] | |
| # Define a string variable to store the image path. | |
| ImageUrl = dataDir + "logo.jpg" | |
| # Get the picture into the streams. | |
| fs = open(ImageUrl, "rb") | |
| # Define a byte array. | |
| imageData = bytearray(utils.filesize(fs)) | |
| # Obtain the picture into the array of bytes from streams. | |
| fs.readinto(imageData) | |
| # Close the stream. | |
| fs.close() | |
| # Get an excel file path in a variable. | |
| path = dataDir + "book1.xls" | |
| # Get the file into the streams. | |
| fs = open(path, "rb") | |
| # Define an array of bytes. | |
| objectData = bytearray(utils.filesize(fs)) | |
| # Store the file from streams. | |
| fs.readinto(objectData) | |
| # Close the stream. | |
| fs.close() | |
| # Add an Ole object into the worksheet with the image | |
| # Shown in MS Excel. | |
| sheet.ole_objects.add(14, 3, 200, 220, imageData) | |
| # Set embedded ole object data. | |
| sheet.ole_objects[0].object_data = objectData | |
| # Save the excel file | |
| workbook.save(dataDir + "output.out.xls") |
Extracting OLE Objects in the Workbook
The following example shows how to extract OLE Objects in a Workbook. The example gets different OLE objects from an existing XLS file and saves different files (DOC, XLS, PPT, PDF, etc.) based on the OLE object’s file format type.
After running the code, we can save different files based on their respective OLE Objects format types.
| from aspose.cells import FileFormatType, Workbook | |
| from io import BytesIO | |
| # For complete examples and data files, please go to https:# github.com/aspose-cells/Aspose.Cells-for-.NET | |
| # The path to the documents directory. | |
| dataDir = RunExamples.GetDataDir(".") | |
| # Open the template file. | |
| workbook = Workbook(dataDir + "book1.xls") | |
| # Get the OleObject Collection in the first worksheet. | |
| oles = workbook.worksheets[0].ole_objects | |
| # Loop through all the oleobjects and extract each object. | |
| # In the worksheet. | |
| for i in range(len(oles)): | |
| ole = oles[i] | |
| # Specify the output filename. | |
| fileName = dataDir + "ole_" + str(i) + "." | |
| # Specify each file format based on the oleobject format type. | |
| if ole.file_format_type == FileFormatType.DOC: | |
| fileName = "doc" | |
| elif ole.file_format_type == FileFormatType.XLSX: | |
| fileName = "Xlsx" | |
| elif ole.file_format_type == FileFormatType.PPT: | |
| fileName = "Ppt" | |
| elif ole.file_format_type == FileFormatType.PDF: | |
| fileName = "Pdf" | |
| elif ole.file_format_type == FileFormatType.UNKNOWN: | |
| fileName = "Jpg" | |
| # Save the oleobject as a new excel file if the object type is xls. | |
| if ole.file_format_type == FileFormatType.XLSX: | |
| ms = BytesIO() | |
| ms.write(ole.object_data) | |
| oleBook = Workbook(ms) | |
| oleBook.settings.is_hidden = False | |
| oleBook.save(dataDir + "Excel_File" + str(i) + ".out.xlsx") | |
| else: | |
| fs = open(fileName, "wb") | |
| fs.write(ole.object_data) | |
| fs.close() |
Extracting Embedded MOL File
Aspose.Cells for Python via .NET supports extracting objects of uncommon types like MOL(Molecular data file containing information about atoms and bonds). The following code snippet demonstrates extracting embedded MOL file and saving it to disk by using this sample excel file.
| from aspose.cells import Workbook | |
| # For complete examples and data files, please go to https:# github.com/aspose-cells/Aspose.Cells-for-.NET | |
| # directories | |
| SourceDir = RunExamples.Get_SourceDirectory() | |
| outputDir = RunExamples.Get_OutputDirectory() | |
| workbook = Workbook(SourceDir + "EmbeddedMolSample.xlsx") | |
| index = 1 | |
| for sheet in workbook.worksheets: | |
| oles = sheet.ole_objects | |
| for ole in oles: | |
| fileName = outputDir + "OleObject" + str(index) + ".mol " | |
| fs = open(fileName, "wb") | |
| fs.write(ole.object_data) | |
| fs.close() | |
| index | |
| index = index + 1 |