python处理excel数据(python从零基础开始处理excel)(1)

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各种数据需要导入Excel?多个Excel要合并?目前,Python处理Excel文件有很多库,openpyxl算是其中功能和性能做的比较好的一个。接下来我将为大家介绍各种Excel操作。

打开Excel文件

新建一个Excel文件

>>> from openpyxl import Workbook
>>> wb = Workbook

打开现有Excel文件

>>> from openpyxl import load_workbook
>>> wb2 = load_workbook('test.xlsx')

打开大文件时,根据需求使用只读或只写模式减少内存消耗。

wb = load_workbook(filename='large_file.xlsx', read_only=True)

wb = Workbook(write_only=True)

获取、创建工作表

获取当前活动工作表:

>>> ws = wb.active

创建新的工作表:

>>> ws1 = wb.create_sheet("Mysheet") # insert at the end (default)
# or
>>> ws2 = wb.create_sheet("Mysheet", 0) # insert at first position
# or
>>> ws3 = wb.create_sheet("Mysheet", -1) # insert at the penultimate position

使用工作表名字获取工作表:

>>> ws3 = wb["New Title"]

获取所有的工作表名称:

>>> print(wb.sheetnames)
['Sheet2', 'New Title', 'Sheet1']
使用for循环遍历所有的工作表:

>>> for sheet in wb:
... print(sheet.title)

保存

保存到流中在网络中使用:

>>> from tempfile import NamedTemporaryFile
>>> from openpyxl import Workbook
>>> wb = Workbook
>>> with NamedTemporaryFile as tmp:
wb.save(tmp.name)
tmp.seek(0)
stream = tmp.read
保存到文件:

>>> wb = Workbook
>>> wb.save('balances.xlsx')
保存为模板:

>>> wb = load_workbook('document.xlsx')
>>> wb.template = True
>>> wb.save('document_template.xltx')

单元格

单元格位置作为工作表的键直接读取:

>>> c = ws['A4']

为单元格赋值:

>>> ws['A4'] = 4
>>> c.value = 'hello, world'

多个单元格可以使用切片访问单元格区域:

>>> cell_range = ws['A1':'C2']

使用数值格式:

>>> # set date using a Python datetime
>>> ws['A1'] = datetime.datetime(2010, 7, 21)
>>>
>>> ws['A1'].number_format
'yyyy-mm-dd h:mm:ss'

使用公式:

>>> # add a simple formula
>>> ws["A1"] = "=SUM(1, 1)"

合并单元格时,除左上角单元格外,所有单元格都将从工作表中删除:

>>> ws.merge_cells('A2:D2')
>>> ws.unmerge_cells('A2:D2')
>>>
>>> # or equivalently
>>> ws.merge_cells(start_row=2, start_column=1, end_row=4, end_column=4)
>>> ws.unmerge_cells(start_row=2, start_column=1, end_row=4, end_column=4)

行、列

可以单独指定行、列、或者行列的范围:

>>> colC = ws['C']
>>> col_range = ws['C:D']
>>> row10 = ws[10]
>>> row_range = ws[5:10]

可以使用Worksheet.iter_rows方法遍历行:

>>> for row in ws.iter_rows(min_row=1, max_col=3, max_row=2):
... for cell in row:
... print(cell)
<Cell Sheet1.A1>
<Cell Sheet1.B1>
<Cell Sheet1.C1>
<Cell Sheet1.A2>
<Cell Sheet1.B2>
<Cell Sheet1.C2>

同样的Worksheet.iter_cols方法将遍历列:

>>> for col in ws.iter_cols(min_row=1, max_col=3, max_row=2):
... for cell in col:
... print(cell)
<Cell Sheet1.A1>
<Cell Sheet1.A2>
<Cell Sheet1.B1>
<Cell Sheet1.B2>
<Cell Sheet1.C1>
<Cell Sheet1.C2>

遍历文件的所有行或列,可以使用Worksheet.rows属性:

>>> ws = wb.active
>>> ws['C9'] = 'hello world'
>>> tuple(ws.rows)
((<Cell Sheet.A1>, <Cell Sheet.B1>, <Cell Sheet.C1>),
(<Cell Sheet.A2>, <Cell Sheet.B2>, <Cell Sheet.C2>),
(<Cell Sheet.A3>, <Cell Sheet.B3>, <Cell Sheet.C3>),
(<Cell Sheet.A4>, <Cell Sheet.B4>, <Cell Sheet.C4>),
(<Cell Sheet.A5>, <Cell Sheet.B5>, <Cell Sheet.C5>),
(<Cell Sheet.A6>, <Cell Sheet.B6>, <Cell Sheet.C6>),
(<Cell Sheet.A7>, <Cell Sheet.B7>, <Cell Sheet.C7>),
(<Cell Sheet.A8>, <Cell Sheet.B8>, <Cell Sheet.C8>),
(<Cell Sheet.A9>, <Cell Sheet.B9>, <Cell Sheet.C9>))

或Worksheet.columns属性:

>>> tuple(ws.columns)
((<Cell Sheet.A1>,
<Cell Sheet.A2>,
<Cell Sheet.A3>,
<Cell Sheet.A4>,
<Cell Sheet.A5>,
<Cell Sheet.A6>,
...
<Cell Sheet.B7>,
<Cell Sheet.B8>,
<Cell Sheet.B9>),
(<Cell Sheet.C1>,
<Cell Sheet.C2>,
<Cell Sheet.C3>,
<Cell Sheet.C4>,
<Cell Sheet.C5>,
<Cell Sheet.C6>,
<Cell Sheet.C7>,
<Cell Sheet.C8>,
<Cell Sheet.C9>))

使用Worksheet.append或者迭代使用Worksheet.cell新增一行数据:

>>> for row in range(1, 40):
... ws1.append(range(600))

>>> for row in range(10, 20):
... for col in range(27, 54):
... _ = ws3.cell(column=col, row=row, value="{0}".format(get_column_letter(col)))

插入操作比较麻烦。可以使用Worksheet.insert_rows插入一行或几行:

>>> from openpyxl.utils import get_column_letter
>>> ws.insert_rows(7)
>>> row7 = ws[7]
>>> for col in range(27, 54):
... _ = ws3.cell(column=col, row=7, value="{0}".format(get_column_letter(col)))

Worksheet.insert_cols操作类似。Worksheet.delete_rows和Worksheet.delete_cols用来批量删除行和列。

只读取值

使用Worksheet.values属性遍历工作表中的所有行,但只返回单元格值:

for row in ws.values:
for value in row:
print(value)

Worksheet.iter_rows和Worksheet.iter_cols可以设置values_only参数来仅返回单元格的值:

>>> for row in ws.iter_rows(min_row=1, max_col=3, max_row=2, values_only=True):
... print(row)
(None, None, None)
(None, None, None)