python中csv文件处理(读写csv文件)

1. 读取csv文件

import csv with open('stock.csv','r') as fp: reader = csv.reader(fp) # reader是一个迭代器，可以进行遍历 titles = next(reader) for x in reader: print(x[0]) print(x[1]) print(x[2])

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。那么可以使用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['name']) print(x['age']) print(x['status'])

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，这个是写入一行。一个是writerows，这个是写入多行。示例代码如下：

import csv headers = ['name','age','status'] values = [ ('zff',22,'single'), ('myh',20,'double'), ('gx',21,'double') ] with open('test.csv','w',newline='') as fp: writer = csv.writer(fp) writer.writerow(headers) writer.writerows(values)

也可以使用字典的方式把数据写入进去。这时候就需要使用DictWriter了。示例代码如下：

import csv headers = ['name','age','status'] values = [ {"name":'wenn',"age":20,"status":'double'}, {"name":'abc',"age":30,"status":'double'} ] with open('test.csv','w',newline='') as fp: writer = csv.DictWriter(fp,headers) writer = csv.writeheader() writer.writerow({'name':'zhiliao',"age":18,"status":'111'}) writer.writerows(values)