Python 3基础教程24-读取csv文件

本文来介绍用Python读取csv文件。什么是csv（Comma-Separated Values），也叫逗号分割值，如果你安装了excel，默认会用excel打开csv文件。

1. 我们先制作一个csv文件，example.csv

2. 看看如何用Python来读取这个文件

import csv

with open(r'C:\Users\Anthony\Desktop\example.csv') as csvfile:
    readCSV = csv.reader(csvfile, delimiter=',')
    for row in readCSV:
        print(row)
 

运行输出效果

['city', 'password', 'day']
['Beijing', 'DJOYnieT8234jlsK', '1']
['Shanghai', 'DJOYnieT8234jlsK', '2']
['Guangzhou', 'DJOYnieT8234jlsK', '3']
['Shenzhen', 'DJOYnieT8234jlsK', '1']
>>>

3. 进入到某一个单元格

 import csv

 with open(r'C:\Users\Anthony\Desktop\example.csv') as csvfile:
     readCSV = csv.reader(csvfile, delimiter=',')
     for row in readCSV:
         # print(row)
         print(row[0])
         print(row[0],row[1])

4. 如何单独每列输出打印

 import csv

 with open(r'C:\Users\Anthony\Desktop\example.csv') as csvfile:
     readCSV = csv.reader(csvfile, delimiter=',')
     citys = []
     password = []
     days = []
     for row in readCSV:
         city = row[0]
         paword = row[1]
         day = row[2]

         citys.append(city)
         password.append(paword)
         days.append(day)

     print(citys)
     print(password)
     print(days)

上面这个r表示不需要转义，原义输出，因为上面有\，反斜杠默认是转义，所以需要添加r
输出效果

>>>
================= RESTART: C:\Users\Anthony\Desktop\demo.py =================
['city', 'Beijing', 'Shanghai', 'Guangzhou', 'Shenzhen']
['password', 'DJOYnieT8234jlsK', 'DJOYnieT8234jlsK', 'DJOYnieT8234jlsK', 'DJOYnieT8234jlsK']
['day', '1', '2', '3', '1']
>>>