How to use Application.FileDialog in the xlwings API way

The Application.FileDialog property in Excel’s object model is a powerful tool for displaying file dialog boxes, enabling users to select files or folders. In xlwings, this functionality is accessed through the api property, which provides direct access to the underlying Excel VBA object model. This allows Python scripts to leverage Excel’s built-in dialog interfaces for file operations, enhancing user interaction within automated workflows.

Functionality:
The FileDialog property returns a FileDialog object, which represents a single instance of a file dialog box. It can be used to display dialogs for opening files, saving files, selecting folders, or choosing file pickers. This is particularly useful for scripts that require user input for file paths, making automation more interactive and flexible.

Syntax in xlwings:
To use FileDialog in xlwings, you first access the Excel Application object via xlwings, then call the FileDialog property. The basic syntax is:

file_dialog = xw.apps.active.api.FileDialog(fileDialogType)

Here, fileDialogType is a required parameter that specifies the type of dialog to display. It accepts integer values from the MsoFileDialogType enumeration, which can be referenced via constants or direct integers. Common values include:

• 1 (or msoFileDialogOpen): For opening files.
• 2 (or msoFileDialogSaveAs): For saving files.
• 3 (or msoFileDialogFilePicker): For selecting files.
• 4 (or msoFileDialogFolderPicker): For selecting folders.

Once the FileDialog object is obtained, you can configure properties like InitialFileName or Title, and then display the dialog using the Show method. The Show method returns -1 if the user clicks OK, and 0 if canceled. Selected items can be retrieved via the SelectedItems property.

Example Code:
Below is an xlwings code example that demonstrates using FileDialog to open a file picker dialog, allowing users to select multiple Excel files, and then print the selected file paths.

import xlwings as xw

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

# Get the FileDialog object for file picking
file_dialog = app.api.FileDialog(3) # 3 corresponds to msoFileDialogFilePicker

# Set dialog properties
file_dialog.AllowMultiSelect = True
file_dialog.Title = "Select Excel Files"
file_dialog.InitialFileName = "C:\\Users\\Example\\Documents\\"

# Display the dialog and check user action
if file_dialog.Show() == -1: # User clicked OK
    selected_files = file_dialog.SelectedItems
    for file_path in selected_files:
        print(f"Selected file: {file_path}")
else:
    print("Dialog was canceled by the user.")

# Note: Ensure Excel is open and xlwings is properly installed.