保存数据到csv

csv 逗号分隔值

一、写入

1、列表

单行添加

import csv
 
#
 
with open(file='a.csv', mode='w', encoding='utf-8', newline='') as f:
    write = csv.writer(f)
    write.writerow(['id', 'name', 'age'])
    write.writerow(['', 'tom', 23])
    write.writerow(['', 'alex', 34])
    write.writerow(['', 'Bob', 16])
 
# newline='' 作用去除行，若没有每添加一条数据，添加一空行

批量添加

import csv
 
#
header = ['id', 'name', 'age']
body = [
    ['', 'tom', 23],
    ['', 'alex', 34],
    ['', 'Bob', 16]
]
 
with open(file='b.csv', mode='w', encoding='utf-8', newline='') as f:
    write = csv.writer(f)
    write.writerow(header)
    write.writerows(body)
 
# 注意：批量添加用writerows()

2、字典

单行添加

import csv
 
#
header = ['id', 'name', 'age']
 
with open(file='c.csv', mode='w', encoding='utf-8', newline='') as f:
    write = csv.DictWriter(f, fieldnames=header)
    write.writeheader()
    write.writerow({'id': '', 'name': 'tom', 'age': 23})
    write.writerow({'id': '', 'name': 'alex', 'age': 34})
    write.writerow({'id': '', 'name': 'Bob', 'age': 45})

批量添加

import csv
 
#
header = ['id', 'name', 'age']
 
body_dic = [
    {'id': '', 'name': 'tom', 'age': 23},
    {'id': '', 'name': 'alex', 'age': 34},
    {'id': '', 'name': 'Bob', 'age': 45}
]
 
with open(file='d.csv', mode='w', encoding='utf-8', newline='') as f:
    write = csv.DictWriter(f, fieldnames=header)
    write.writeheader()
    write.writerows(body_dic)

二、读取

1、列表

import csv
 
#
 
with open(file='d.csv', mode='r', encoding='utf-8', newline='') as f:
    reader = csv.reader(f)
    for row in reader:
        print(row)

2、字典

import csv
 
#
 
with open(file='d.csv', mode='r', encoding='utf-8', newline='') as f:
    reader = csv.DictReader(f)
    for row in reader:
        print(dict(row))