Python如何读写CSV文件

import csv

with open('a.csv') as csv_file:
  csv_reader = csv.reader(csv_file,delimiter=',')
  line_count = 0

  for row in csv_reader:
    if line_count == 0:
      print(f'Column names are {", ".join(row)}')
      line_count += 1
    else:
      print(f'\t{row[0]} works in the {row[1]} department, and was born in {row[2]}.')
      line_count += 1
    print(f'Processed {line_count} lines.')

import csv

with open('b.csv', mode='w') as employee_file:
  employee_writer = csv.writer(employee_file, delimiter=',', quotechar='"', quoting=csv.QUOTE_MINIMAL)

  employee_writer.writerow(['John Smith', 'Accounting', 'November'])
  employee_writer.writerow(['Erica Meyers', 'IT', 'March'])

import pandas
df = pandas.read_csv('hrdata.csv')
print(df)

# 输出的df

#       Name Hire Date  Salary Sick Days remaining
# 0 Graham Chapman 03/15/14 50000.0          10
# 1   John Cleese 06/01/15 65000.0          8
# 2    Eric Idle 05/12/14 45000.0          10
# 3   Terry Jones 11/01/13 70000.0          3
# 4  Terry Gilliam 08/12/14 48000.0          7
# 5  Michael Palin 05/23/13 66000.0          8

import pandas
df = pandas.read_csv('hrdata.csv', 
      index_col='Employee', 
      parse_dates=['Hired'],
      header=0, 
      names=['Employee', 'Hired', 'Salary', 'Sick Days'])
df.to_csv('d.csv')

# d.csv文件内容

# Employee,Hired,Salary,Sick Days
# Graham Chapman,2014-03-15,50000.0,10
# John Cleese,2015-06-01,65000.0,8
# Eric Idle,2014-05-12,45000.0,10
# Terry Jones,2013-11-01,70000.0,3
# Terry Gilliam,2014-08-12,48000.0,7
# Michael Palin,2013-05-23,66000.0,8