Losing merged cells border while editing Excel file with openpyxl

Question

I have two sheets in an Excel file and the first one is a cover sheet which I don\'t need to edit. There are a few merged cells in the cover sheet, and when I edit the file usin

Answer 1

I know this is old but I got the same issue and the patch didn't work for me so I found a work around by using the function in the documentation that adds a style for merged cells and then looping on all the merged cells and calling the function on each range

from openpyxl import load_workbook
from openpyxl.styles import Border, Side, PatternFill, Font, GradientFill, 
Alignment

def style_range(ws, cell_range, border=Border(), fill=None, font=None, 
alignment=None):
    """
    Apply styles to a range of cells as if they were a single cell.

    :param ws:  Excel worksheet instance
    :param range: An excel range to style (e.g. A1:F20)
    :param border: An openpyxl Border
    :param fill: An openpyxl PatternFill or GradientFill
    :param font: An openpyxl Font object
    """

    top = Border(top=border.top)
    left = Border(left=border.left)
    right = Border(right=border.right)
    bottom = Border(bottom=border.bottom)

    first_cell = ws[cell_range.split(":")[0]]
    if alignment:
        ws.merge_cells(cell_range)
        first_cell.alignment = alignment

    rows = ws[cell_range]
    if font:
        first_cell.font = font

    for cell in rows[0]:
        cell.border = cell.border + top
    for cell in rows[-1]:
        cell.border = cell.border + bottom

    for row in rows:
        l = row[0]
        r = row[-1]
        l.border = l.border + left
        r.border = r.border + right
        if fill:
            for c in row:
                c.fill = fill

file = 'file.xlsx'

wb = load_workbook(file)
ws = wb['Table 1']

thin = Side(border_style="thin", color="000000")
border = Border(top=thin, left=thin, right=thin, bottom=thin)

for range in ws.merged_cells.ranges:
    style_range(ws, str(range), border=border)

wb.save('newExcel.xlsx')