Python csv 文件读写
Table of Contents
1 读取 csv 文件
import csv
with open('stock.csv','r') as fp:
reader = csv.reader(fp)
titles = next(reader)
for x in reader:
print(x)
这样操作,以后获取数据的时候,就要通过下表来获取数据。如果想要在获取数据的时候通过标题来获取,可以使用 DictReader
。示例代码如下:
import csv
with open('stock.csv','r') as fp:
reader = csv.DictReader(fp)
for x in reader:
print(x['turnoverVol'])
2 写入数据到 csv 文件
写入数据到csv文件,需要创建一个 writer
对象,主要用到两个方法。一个是 writerow
写入一行。一个是 writerows
写入多行。示例代码如下:
import csv
headers = ['name','age','classroom']
values = [
('zhiliao',18,'111'),
('wena',20,'222'),
('bbc',21,'111')]
with open('test.csv','w',newline='') as fp:
writer = csv.writer(fp)
writer.writerow(headers)
writer.writerows(values)
使用 DictWriter
可以使用字典的方式把数据写进去。示例代码如下:
import csv
headers = ['name','age','classroom']
values = [
{"name":'wenn',"age":20, "classroom":'222'},
{"name":'abc' ,"age":30, "classroom":'333'}]
with open('test.csv','w',newline='') as fp:
writer = csv.DictWriter(fp,headers)
writer = csv.writeheader()
writer.writerow({'name':'zhiliao',"age":18,"classroom":'111'})
writer.writerows(values)