XlsxWriter撰写日期为数字

Question

I am writing date to a file and i am using:

date.strftime('%m/%d/%Y')

and i am writing date object to excel file:

worksheet.write(row_count, column_count, r, formatter)

where formatter is aligning it in the middle and r is the object in the current loop.

It shows like 10/28/2016 but i want it to be saved as a number value (like 42871 for example). Is there any way this to happen within code and not manually in excel?

Answer 1

The number value in Excel is what I'm assuming as the days since epoch, which in this case is January 1st, 1900. Refer to here . However, in practice you would want to use Dec 30, 1899 to account for leap years. All you have to do is run a diff check and then get the days from the epoch.

Assuming your date is 10/28/2016:

>>> from datetime import date
>>> new_value = (date(2016,10,28) - date(1899,12,30)).days
42671

Therefore, before you write your rows, just do some upfront calculation:

new_value = (your_date_in_the_row - date(1899,12,30)).days

Answer 2

As explained in the XlsxWriter documentation on Working with Dates and Times a date in Excel is just a number with a format. If you omit the format you get the number:

from datetime import datetime
import xlsxwriter

workbook = xlsxwriter.Workbook('datetimes.xlsx')
worksheet = workbook.add_worksheet()

# Widen the first column so that the dates are visible.
worksheet.set_column('A:A', 20)

# Create a datetime object.
date_time = datetime.strptime('2017-05-16', '%Y-%m-%d')

# Create a format for the date or time.
date_format = workbook.add_format({'num_format': 'd mmmm yyyy'})

worksheet.write('A1', date_time, date_format)
worksheet.write('A2', date_time             )

workbook.close()

Output: