How to use Application.CheckSpelling in the xlwings API way

The Application.CheckSpelling method in Excel is a useful tool for checking the spelling of a single word or a text string programmatically. When accessed through the xlwings library in Python, it provides a way to integrate Excel’s built-in spelling checker into automated scripts and data processing workflows. This can be particularly valuable for validating user inputs, cleaning text data, or ensuring consistency in reports before they are finalized.

In xlwings, the CheckSpelling method is called from the Application object. The syntax follows the pattern of the Excel Object Model, adapted for Python. The basic xlwings API call format is:

app.api.CheckSpelling(Word, CustomDictionary, IgnoreUppercase, MainDictionary, CustomDictionary2, CustomDictionary3, CustomDictionary4, CustomDictionary5, CustomDictionary6, CustomDictionary7, CustomDictionary8, CustomDictionary9, CustomDictionary10)

The parameters are:

• Word (Required, String): The word or text string you want to check.
• CustomDictionary (Optional, String): The file name of the custom dictionary to examine if the word is not found in the main dictionary. The default is an empty string.
• IgnoreUppercase (Optional, Boolean): True to ignore words in all uppercase letters. False to check them. The default is False.
• MainDictionary (Optional, Variant): This can be a language identifier (e.g., “en-US”) or a constant representing a built-in dictionary. It is often left as an optional argument in xlwings, defaulting to the application’s current language setting.
• CustomDictionary2 to CustomDictionary10 (Optional, String): Additional custom dictionary file names.

The method returns a Boolean value. It returns True if the word is found in at least one of the specified dictionaries, and False if it is not found in any. This allows you to use the method in conditional logic within your Python code.

Here are two practical xlwings code examples:

Example 1: Checking a Single Word
This example checks if the word “Analyzze” is spelled correctly according to Excel’s dictionaries.

import xlwings as xw

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

# Check the spelling of a word
word_to_check = "Analyzze"
is_correct = app.api.CheckSpelling(word_to_check)

if is_correct:
    print(f"'{word_to_check}' is spelled correctly.")
else:
    print(f"'{word_to_check}' is misspelled.")
    # This will output: 'Analyzze' is misspelled.

Example 2: Checking Multiple Words from a List
This example demonstrates iterating through a list of potential product codes or terms, using the spelling checker as a simple validation filter, and ignoring terms that are in all caps.

import xlwings as xw

app = xw.apps.active

term_list = ["Project", "XYZZY", "Maintainance", "API", "Delevopment"]
valid_terms = []
flagged_terms = []

for term in term_list:
    # Check spelling, ignoring words in all uppercase
    if app.api.CheckSpelling(term, IgnoreUppercase=True):
        valid_terms.append(term)
    else:
        flagged_terms.append(term)

print("Terms considered valid:", valid_terms)
print("Terms flagged for review:", flagged_terms)
# Expected output:
# Terms considered valid: ['Project', 'XYZZY', 'API']
# Terms flagged for review: ['Maintainance', 'Delevopment']