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How to use Application.DeferAsyncQueries in the xlwings API way

The DeferAsyncQueries property of the Application object in Excel is a Boolean value that controls whether asynchronous queries (such as those from Power Query or external data connections) are deferred during the workbook’s opening process. When set to True, Excel postpones the execution of these queries until after the workbook has fully opened, which can significantly improve the initial load time, especially for workbooks with complex data connections. When set to False (the default), asynchronous queries run as usual during the opening sequence. This property is particularly useful for automating the opening of large workbooks in xlwings scripts, allowing you to manage performance and data refresh timing programmatically.

Syntax in xlwings:
The property is accessed through the xlwings App object, which represents the Excel Application. The syntax is straightforward:

app.api.DeferAsyncQueries

This property is both readable and writable. You can assign a Boolean value (True or False) to it to change its state.

  • Get the current value: current_state = app.api.DeferAsyncQueries
  • Set the value: app.api.DeferAsyncQueries = True

There are no parameters for this property itself. Its behavior is simply toggled by the Boolean assignment.

Code Example:
The following xlwings code demonstrates a practical use case. It opens a workbook with heavy external data connections, defers the queries to speed up the opening process, performs some other operations, and then manually triggers a refresh of all connections.

import xlwings as xw

# Start Excel application (visible for demonstration)
app = xw.App(visible=True)

# Enable deferral of asynchronous queries before opening the workbook
app.api.DeferAsyncQueries = True

# Open the target workbook
wb = app.books.open(r'C:\Path\To\Your\Large_Workbook.xlsx')

# At this point, the workbook is open, but queries are not yet run.
# Perform other operations, such as reading static data or writing formulas.
sheet = wb.sheets['Report']
summary_value = sheet.range('A1').value
print(f"Initial summary value: {summary_value}")

# Now, disable deferral and refresh all external data connections.
app.api.DeferAsyncQueries = False
wb.api.RefreshAll()

# Wait a moment for refresh to complete, then get updated data.
import time
time.sleep(5) # Simple pause; in production, consider checking query status.
updated_value = sheet.range('A1').value
print(f"Refreshed summary value: {updated_value}")

# Save and close
wb.save()
wb.close()
app.quit()

How to use Application.DefaultWebOptions in the xlwings API way

The Application.DefaultWebOptions property in Excel’s object model provides access to a DefaultWebOptions object, which contains global settings for how Excel handles web-related features, such as saving workbooks as web pages or interacting with web queries. Through xlwings, you can access and modify these settings to control the default behavior for web publishing, encoding, and other web-specific options. This is particularly useful when automating the generation of web content from Excel data or ensuring consistency in web output formats.

Functionality:
The DefaultWebOptions object allows you to set properties that affect web-related operations. Key properties include:

  • Encoding: Specifies the character encoding for web pages (e.g., utf-8, gb2312).
  • PixelsPerInch: Controls the screen resolution for images in web pages.
  • OrganizeInFolder: Determines whether supporting files are saved in a separate folder when saving as a web page.
  • TargetBrowser: Sets the target browser version for compatibility.
  • DownloadComponents: Specifies whether to download Office Web Components.

Syntax in xlwings:
In xlwings, you access DefaultWebOptions via the Application object. Since xlwings uses the underlying Excel object model through COM, the syntax mirrors VBA but is adapted for Python. The general format is:

app = xw.apps.active # Get the active Excel application
web_options = app.api.DefaultWebOptions

Once you have the web_options object, you can get or set its properties. For example, to set the encoding:

web_options.Encoding = "utf-8"

Note that DefaultWebOptions is a property, not a method, so it doesn’t take parameters directly. However, its properties may have specific values. For instance, TargetBrowser can be set using constants like xlBrowserV4 (for older browsers) or xlBrowserIE6 (for Internet Explorer 6). In xlwings, you can use the integer equivalents or import constants from win32com.client.constants if available.

Example Usage:
Here is a code example that demonstrates how to configure DefaultWebOptions using xlwings to prepare a workbook for web publishing. This script sets various properties and then saves the active workbook as a web page with the specified settings.

import xlwings as xw

# Connect to the active Excel application
app = xw.apps.active

# Access the DefaultWebOptions object
web_options = app.api.DefaultWebOptions

# Configure web properties
web_options.Encoding = "utf-8" # Set character encoding to UTF-8
web_options.PixelsPerInch = 96 # Set screen resolution for images
web_options.OrganizeInFolder = True # Save supporting files in a separate folder
web_options.TargetBrowser = 3 # Use constant for Internet Explorer 6 (value 3)
web_options.DownloadComponents = False # Disable downloading Office Web Components

# Save the active workbook as a web page with these settings
workbook = app.books.active
workbook.api.SaveAs(Filename="C:\\Output\\webpage.html", FileFormat=44) # FileFormat 44 is for web page

How to use Application.DefaultSheetDirection in the xlwings API way

The Application.DefaultSheetDirection property in Excel’s object model allows developers to set or retrieve the default direction in which new worksheets are laid out within a workbook. This property influences whether the sheet content is displayed from left-to-right (typical for languages like English) or right-to-left (common for languages such as Arabic or Hebrew). It is particularly useful in internationalized applications where the user interface must adapt to different reading orientations. In xlwings, this property can be accessed and modified through the api property of the App object, providing a programmatic way to control sheet direction directly from Python.

Syntax in xlwings:

app.api.DefaultSheetDirection

This property is both readable and writable. It accepts integer values that correspond to specific direction settings:

  • xlLTR (value: -5003): Sets the default direction to left-to-right.
  • xlRTL (value: -5004): Sets the default direction to right-to-left.

These constants are part of the Excel enumeration XlSheetDirection. In xlwings, you can use the integer values directly or import the constants from the win32com.client.constants module if working on Windows with COM support, though xlwings typically abstracts this. The property applies at the application level, meaning it affects all new workbooks and sheets created during the session until changed.

Code Examples:

  1. Reading the Current Default Sheet Direction:
import xlwings as xw
app = xw.App(visible=False)
current_direction = app.api.DefaultSheetDirection
print(f"Default sheet direction: {current_direction}") # Output: -5003 for left-to-right
app.quit()

This example retrieves the current setting, which defaults to left-to-right in most installations.

  1. Setting the Default Sheet Direction to Right-to-Left:
import xlwings as xw
app = xw.App(visible=False)
app.api.DefaultSheetDirection = -5004 # xlRTL for right-to-left
# Create a new workbook to see the effect
wb = app.books.add()
ws = wb.sheets[0]
print(f"New sheet direction set to: {app.api.DefaultSheetDirection}")
wb.save('right_to_left_sheet.xlsx')
app.quit()

After setting the property, any new worksheets will adopt the right-to-left layout, affecting text alignment and sheet navigation.

  1. Toggling Between Directions Based on User Input:
import xlwings as xw
def set_sheet_direction(direction='LTR'):
app = xw.App(visible=False)
if direction.upper() == 'RTL':
    app.api.DefaultSheetDirection = -5004
else:
    app.api.DefaultSheetDirection = -5003
    wb = app.books.add()
    print(f"Sheet direction configured for {direction}.")
app.quit()
set_sheet_direction('RTL')

How to use Application.DefaultSaveFormat in the xlwings API way

The Application.DefaultSaveFormat property in Excel’s object model is a read/write property that determines the default file format used when saving a new workbook. This property influences the file format (e.g., .xlsx, .xls, .csv) that Excel will default to in the “Save As” dialog for a new, unsaved workbook. It does not change the format of already saved workbooks. In xlwings, this property is accessed via the Application object, allowing automation scripts to programmatically set or retrieve the default save format, ensuring consistency in file operations across automated Excel processes.

Syntax in xlwings:
The property is accessed through the app object (an instance of xlwings’ App). The syntax is straightforward, as it maps directly to the Excel object model:

  • To get the current default save format:
default_format = app.api.DefaultSaveFormat
  • To set a new default save format:
app.api.DefaultSaveFormat = format_value

Here, app refers to the xlwings App instance (e.g., app = xw.App() or xw.apps.active). The format_value is an integer corresponding to the Excel file format constant. xlwings uses the Excel object model’s constants, which can be referenced via the app.api interface. Common values include:

  • 51: xlOpenXMLWorkbook (.xlsx, without macros)
  • 52: xlOpenXMLWorkbookMacroEnabled (.xlsm, with macros)
  • 50: xlExcel12 (Excel Binary Workbook .xlsb)
  • 6: xlCSV (CSV format)
  • -4143: xlWorkbookNormal (legacy .xls format in older Excel versions)
    These constants are part of the Excel enumeration XlFileFormat. In xlwings, you can use the integer values directly or, for clarity, define them as variables (e.g., xlOpenXMLWorkbook = 51). Note that the property is specific to the Excel application instance, so changes apply to all workbooks under that instance.

Examples:
Below are practical xlwings API code examples demonstrating how to use the DefaultSaveFormat property.

  1. Retrieving the Current Default Save Format:
    This example connects to the active Excel instance and prints the current default save format.
import xlwings as xw

# Connect to the active Excel application
app = xw.apps.active

# Get the default save format
current_format = app.api.DefaultSaveFormat
print(f"Current default save format value: {current_format}")

Output might show an integer like 51, indicating .xlsx is the default.

  1. Setting the Default Save Format to .xlsm:
    This example sets the default save format to Excel Macro-Enabled Workbook (.xlsm) for new workbooks.
import xlwings as xw

# Start a new Excel instance (or use active)
app = xw.App(visible=False) # Run in background

# Define the format value for .xlsm
xlOpenXMLWorkbookMacroEnabled = 52

# Set the default save format
app.api.DefaultSaveFormat = xlOpenXMLWorkbookMacroEnabled

# Verify the change
print(f"Default save format set to: {app.api.DefaultSaveFormat}")

# Clean up: close the app without saving
app.quit()

After running this, any new workbook created in this Excel instance will default to .xlsm when saved for the first time.

  1. Using DefaultSaveFormat in a Workflow:
    This example integrates DefaultSaveFormat into a script that creates a workbook and saves it, leveraging the default format.
import xlwings as xw

# Launch Excel and set default to CSV for data export tasks
app = xw.App(visible=True)
app.api.DefaultSaveFormat = 6 # xlCSV

# Add a new workbook
wb = app.books.add()
sheet = wb.sheets[0]
sheet.range('A1').value = [['Data', 'Value'], [1, 100], [2, 200]]

# Save the workbook; it will default to CSV in the Save As dialog
# Note: This property doesn't auto-save; it sets the dialog default.
wb.save('new_data') # User may see .csv as default in the dialog

# Close
wb.close()
app.quit()

How to use Application.DefaultFilePath in the xlwings API way

The DefaultFilePath property of the Application object in Excel’s object model is a crucial setting for managing file paths. In xlwings, this property allows you to get or set the default folder path that Excel uses when opening or saving files through its standard dialog boxes. This is particularly useful for automating workflows where you need to ensure that Excel points to a specific directory by default, enhancing consistency and efficiency in file operations.

Functionality:
The DefaultFilePath property controls the initial directory displayed in the Open and Save As dialog boxes within Excel. By setting this property, you can direct users or automated scripts to a predefined location, reducing errors from manual navigation. It does not affect the current workbook’s path but influences the default behavior of Excel’s file dialogs.

Syntax in xlwings:
In xlwings, you access the DefaultFilePath property through the app object, which represents the Excel application. The syntax is straightforward:

  • To get the current default file path: app.api.DefaultFilePath
  • To set a new default file path: app.api.DefaultFilePath = "your_path_here"

Here, app is an instance of xw.App in xlwings, and .api provides direct access to the underlying Excel object model. The property is a string representing the full path to the directory. For example, on Windows, it might look like "C:\\Users\\Username\\Documents". Ensure the path exists and is accessible; otherwise, setting it may cause errors.

Parameters:
The DefaultFilePath property does not take parameters directly. When setting it, assign a string value with the desired path. The path can be absolute or relative, but it’s recommended to use absolute paths for reliability. In Excel, this property corresponds to the setting found under File > Options > Save > Default local file location.

Code Examples:
Here are practical examples using xlwings to work with the DefaultFilePath property:

  1. Getting the current default file path:
import xlwings as xw

# Connect to the active Excel instance or start a new one
app = xw.apps.active if xw.apps.active else xw.App()
# Get the current default file path
current_path = app.api.DefaultFilePath
print(f"Current default file path: {current_path}")
# Close the app if it was started in this script
if not xw.apps.active:
    app.quit()
  1. Setting a new default file path:
import xlwings as xw

# Start a new Excel instance
app = xw.App(visible=False) # Run in background for automation
# Set the default file path to a specific directory
new_path = "C:\\MyProjects\\ExcelFiles"
app.api.DefaultFilePath = new_path
print(f"Default file path set to: {new_path}")
# Verify by getting the path again
verified_path = app.api.DefaultFilePath
print(f"Verified path: {verified_path}")
# Save or open a file to see the effect in dialogs (optional)
app.quit()
  1. Using in a script to standardize file operations:
import xlwings as xw
import os

# Connect to Excel
app = xw.apps.active if xw.apps.active else xw.App(visible=False)
# Set default path to a project directory
project_dir = os.path.expanduser("~\\Documents\\MyExcelWork")
if not os.path.exists(project_dir):
    os.makedirs(project_dir) # Create directory if it doesn't exist
    app.api.DefaultFilePath = project_dir
    # Now, any Open or Save As dialog will start in this folder
    print(f"Default path configured for: {project_dir}")
# Example: Open a workbook (this would use the default path in dialog)
# wb = app.books.open('example.xlsx') # Uncomment to test
app.quit()

How to use Application.DecimalSeparator in the xlwings API way

The Application.DecimalSeparator property in Excel’s object model is a crucial setting for controlling how decimal numbers are formatted and interpreted in a spreadsheet. In xlwings, this property can be accessed and modified to ensure that numerical data is handled correctly according to regional or specific formatting requirements. This is particularly important when dealing with international datasets or when automating processes that must adhere to a particular decimal notation standard, such as using a comma instead of a period in many European locales.

Functionality
The DecimalSeparator property determines the character used to separate the integer part from the fractional part of a number in Excel. By default, this is often a period (.) in systems with English regional settings, but it can be changed to a comma (,) or another character. Adjusting this property affects how numbers are displayed in cells and can influence the parsing of text into numbers. This is a member of the Application object, which represents the entire Excel application instance, allowing global control over decimal formatting.

Syntax
In xlwings, the API provides a direct way to interact with Excel’s COM interface, enabling access to the Application.DecimalSeparator property. The syntax for using this property is straightforward, as it can be both read and written. The property is accessed through the app object, which represents the Excel application.

  • To get the current decimal separator:
decimal_separator = app.api.DecimalSeparator

This returns a string representing the current decimal separator character.

  • To set a new decimal separator:
app.api.DecimalSeparator = ","

This changes the decimal separator to a comma. The value must be a single-character string.

The property does not require any parameters, as it is a simple string attribute. However, when setting it, ensure the character is valid and supported by Excel to avoid unexpected behavior. Note that changing this property may affect other formatting settings, so it’s advisable to test in a controlled environment.

Code Examples
Here are practical examples of using the DecimalSeparator property with xlwings:

  1. Retrieving the Current Decimal Separator:
    This example demonstrates how to read the current decimal separator setting from an Excel application instance.
import xlwings as xw

# Connect to the active Excel instance or start a new one
app = xw.apps.active

# Get the current decimal separator
current_separator = app.api.DecimalSeparator
print(f"The current decimal separator is: '{current_separator}'")
  1. Changing the Decimal Separator and Formatting Numbers:
    In this example, we change the decimal separator to a comma and then enter a number into a cell to see the effect.
import xlwings as xw

# Start a new Excel instance
app = xw.App()
wb = app.books.add()
sheet = wb.sheets[0]

# Set the decimal separator to a comma
app.api.DecimalSeparator = ","

# Enter a number in a cell
sheet.range("A1").value = 1234.56

# Check the displayed value in the cell (it may show as 1234,56 depending on formatting)
displayed_value = sheet.range("A1").value
print(f"The value in A1 is displayed as: {displayed_value}")

# Close the workbook and quit Excel
wb.close()
app.quit()
  1. Resetting to Default Separator:
    This example shows how to revert to the default decimal separator, typically a period, after making changes.
import xlwings as xw

app = xw.apps.active

# Assume the separator was previously changed to a comma
app.api.DecimalSeparator = ","

# Reset to the default (period)
app.api.DecimalSeparator = "."

# Verify the change
print(f"Decimal separator reset to: '{app.api.DecimalSeparator}'")

How to use Application.DDEAppReturnCode in the xlwings API way

The DDEAppReturnCode property of the Application object in Excel is a read-only property that returns the status code from the last Dynamic Data Exchange (DDE) operation. DDE is an older inter-process communication protocol that allows applications to exchange data. While modern automation typically uses other methods like COM (which xlwings utilizes), this property can be useful for debugging or maintaining legacy Excel applications that interact with DDE servers. The returned integer code indicates success or the specific type of error that occurred during the DDE conversation.

In xlwings, you access this property through the api property of the main App or Book objects, which exposes the raw Excel VBA object model. The syntax is straightforward as it takes no arguments.

Syntax:

xlwings.App.api.DDEAppReturnCode

or, if you have a specific workbook instance:

wb.api.Application.DDEAppReturnCode

Where:

  • The property is accessed directly and returns an Integer value.

The meaning of the return codes is defined by the DDE protocol and the applications involved. Common codes include:

CodeTypical Meaning
0Success / No Error
1The topic was not understood by the server.
2The server did not respond.
7Unknown error.

Important Note: The exact meaning of non-zero codes can vary depending on the DDE server application. You should consult the documentation for the specific application you are communicating with.

Example:
The following xlwings code initiates a DDE operation (a very legacy example) and then checks the return code to see if it was successful.

import xlwings as xw

# Start Excel application
app = xw.App(visible=False)
wb = app.books.add()

# Attempt a legacy DDE operation (e.g., initiating a conversation with "MyServer" on topic "System")
# Note: This is a pseudo-example, as modern xlwings doesn't have direct DDE methods.
# You would typically use the Excel VBA object model via .api for such calls.
try:
    # Simulating a DDE operation using the Excel object model
    # In VBA, this might be: channel = Application.DDEInitiate(app:="MyServer", topic:="System")
    # In xlwings, you would use:
    channel = app.api.DDEInitiate("MyServer", "System")
    print(f"DDE channel opened: {channel}")
except Exception as e:
    print(f"An error occurred during DDEInitiate: {e}")
finally:
    # Check the status code of the last DDE operation
    return_code = app.api.DDEAppReturnCode
    print(f"DDEAppReturnCode: {return_code}")

# Interpret the code
if return_code == 0:
    print("Last DDE operation was successful.")
else:
    print(f"Last DDE operation failed with error code: {return_code}")

# Clean up: Close the channel if it was opened, then quit Excel
if 'channel' in locals():
    app.api.DDETerminate(channel)
wb.close()
app.quit()

How to use Application.DataEntryMode in the xlwings API way

In Excel VBA, the Application.DataEntryMode property is a legacy feature that determines whether Excel is in data entry mode. When enabled, Excel restricts user interaction to only the active data form, preventing access to other parts of the workbook. This is particularly useful for creating controlled data input interfaces, such as custom forms, where you want to limit user actions to specific fields. However, it’s important to note that this property is part of the older Excel object model and may not be widely used in modern applications, as more advanced methods like UserForms or custom dialog boxes are now preferred for data entry tasks.

In xlwings, which provides a Pythonic interface to Excel’s object model, you can access the DataEntryMode property through the Application object. The syntax for accessing this property is straightforward, as it is a read-write property that returns or sets an integer value representing the data entry mode. The values are typically: 0 for normal mode (not in data entry) and 1 for data entry mode. However, the exact behavior and supported values might vary depending on the Excel version, so it’s advisable to refer to Microsoft’s official documentation for detailed specifications.

To use Application.DataEntryMode in xlwings, you first need to establish a connection to an Excel instance or a specific workbook. Here’s the basic syntax:

import xlwings as xw

# Connect to the active Excel application
app = xw.apps.active

# Get the current data entry mode
current_mode = app.api.DataEntryMode
print(f"Current DataEntryMode: {current_mode}")

# Set the data entry mode to 1 (enable data entry mode)
app.api.DataEntryMode = 1

# Perform data entry tasks, then disable data entry mode
app.api.DataEntryMode = 0

In this code, app.api.DataEntryMode is used to interact with the property. The .api attribute in xlwings provides direct access to the underlying Excel object model, allowing you to use properties and methods as defined in VBA. When setting the property, ensure that you are in a context where data entry mode is applicable, such as when a data form is active. Otherwise, setting it might not have any effect or could lead to unexpected behavior.

For a practical example, suppose you are automating a data entry process in Excel where you want to lock the interface to a specific form. You can enable data entry mode to restrict user interactions. Here’s a sample code snippet:

import xlwings as xw
import time

# Start Excel and open a workbook
wb = xw.Book('data_entry.xlsx')
app = wb.app

# Assume a data form is active; enable data entry mode
app.api.DataEntryMode = 1
print("Data entry mode enabled. User restricted to the active form.")

# Simulate data entry tasks, such as filling fields
# For demonstration, wait for 5 seconds to mimic user input
time.sleep(5)

# Disable data entry mode after completion
app.api.DataEntryMode = 0
print("Data entry mode disabled. Normal interaction restored.")

# Save and close the workbook
wb.save()
wb.close()

How to use Application.CutCopyMode in the xlwings API way

The Application.CutCopyMode property in Excel VBA is a property of the Application object that returns or sets the status of the Cut or Copy mode. This property is useful for programmatically determining if a cut or copy operation is currently active, or to cancel such an operation. In xlwings, this property is accessed through the api property of the App object, which provides direct access to the underlying Excel object model. Understanding this property is essential for automating tasks that involve clipboard operations, ensuring that your macros run without interference from pending cut/copy actions.

Functionality:
The primary function of the CutCopyMode property is to manage the state of cut and copy operations within Excel. It can have three possible values:

  • False (or 0): Indicates that no cut or copy operation is currently in progress.
  • True (or 1): Indicates that a copy operation is active. The source range is highlighted with a moving border.
  • xlCut (or 2): Indicates that a cut operation is active. The source range is also highlighted.

By reading this property, your script can check for an active operation before performing actions that might conflict, such as pasting or clearing the clipboard. Setting this property to False is the programmatic equivalent of pressing the ESC key, which cancels the moving border and clears the clipboard state.

Syntax in xlwings:
In xlwings, you interact with this property via the Excel Application object’s COM interface.

  • To Get the current mode:
    current_mode = xw.apps[<app_index>].api.CutCopyMode
    This returns an integer corresponding to the current state.
  • To Set the mode (typically to cancel):
    xw.apps[<app_index>].api.CutCopyMode = False

Parameter & Return Values:
The property is read/write. Its value can be set or returned as a Long integer or a Boolean. The standard values are:

ValueConstant (VBA)Description
0FalseNo cut or copy mode is active.
1TrueCopy mode is active.
2xlCutCut mode is active.

When setting the property, only False (0) is typically used to cancel the mode. Attempting to set it to True or xlCut does not initiate a new cut/copy operation.

Code Examples:

  1. Checking and Reporting the Current Mode:
    This example checks the status and prints a descriptive message.
import xlwings as xw

# Connect to the active Excel instance
app = xw.apps.active

# Get the current CutCopyMode
mode = app.api.CutCopyMode

if mode == 0:
    print("No cut or copy operation is active.")
elif mode == 1:
    print("A copy operation is in progress.")
elif mode == 2:
    print("A cut operation is in progress.")
else:
    print(f"Unknown mode value: {mode}")
  1. Cancelling an Active Cut/Copy Operation:
    This is a common practice to ensure a clean state before executing other operations.
import xlwings as xw

app = xw.apps.active

# Check if a cut/copy mode is active
if app.api.CutCopyMode:
    print("Cancelling the active cut/copy mode.")
    app.api.CutCopyMode = False # Equivalent to pressing ESC

# Now it's safe to proceed, e.g., with a paste operation
# app.api.Selection.PasteSpecial() # Example follow-up action
  1. Integrating into a Larger Workflow:
    This example copies a range, performs a check, and then cancels the mode.
import xlwings as xw

app = xw.apps.active
wb = app.books.active
sheet = wb.sheets[0]

# Perform a copy operation (this activates Copy mode)
sheet.range("A1:B2").copy()

# Verify the mode was activated
if app.api.CutCopyMode == 1:
    print("Range copied successfully. Copy mode is active.")

# ... Perform other tasks ...

# Cancel the copy mode explicitly when done
app.api.CutCopyMode = False
print("Copy mode cleared.")

How to use Application.CustomListCount in the xlwings API way

The CustomListCount member of the Application object in Excel refers to the total number of custom lists available in the Excel application. Custom lists are user-defined sequences (e.g., a list of department names, product categories, or regional offices) that can be used for autofill and sorting operations. This property is read-only and returns a Long integer representing the count. In xlwings, you can access this property to programmatically determine how many custom lists are currently defined, which is useful for automating tasks that depend on these lists, such as data validation or dynamic range naming based on list entries.

Syntax in xlwings:
The property is accessed through the Application object. In xlwings, you typically start by instantiating an app or using the active app. The syntax is straightforward:

app.custom_list_count

Here, app is an instance of the xlwings App class, representing the Excel application. The property takes no parameters and directly returns an integer value. For example, if you have defined three custom lists in Excel (e.g., “Q1, Q2, Q3, Q4”, “East, West, North, South”, and “Low, Medium, High”), calling app.custom_list_count will return 3.

Example Usage:
Below is a practical xlwings code example that demonstrates how to use the CustomListCount property. This example checks the number of custom lists and prints a message based on the count. It also shows how to iterate through custom lists if needed (though note that accessing individual list details requires other properties like CustomList, which is not covered here as per the focus on CustomListCount).

import xlwings as xw

def check_custom_lists():
# Connect to the active Excel instance or start a new one
app = xw.apps.active # Use the currently active Excel application

# Get the count of custom lists
count = app.custom_list_count

# Output the result
print(f"Number of custom lists available: {count}")

# Example logic based on the count
if count == 0:
    print("No custom lists are defined. Consider creating some for autofill or sorting tasks.")
elif count <= 5:
    print("A moderate number of custom lists are available. Suitable for basic automation.")
else:
    print("Many custom lists are available. Ideal for complex data processing workflows.")

# Optional: Close the app if it was started by xlwings (uncomment if needed)
# app.quit()

# Run the function
if __name__ == "__main__":
check_custom_lists()