Python3 CSV文件

CSV：逗号分隔值，其文件以纯文本形式存储表格数据。一般通用的用法在下面的代码中。

#csv文件的读写
import  csv
#将数据写入csv文件
title = ['编号','姓名','年龄','性别']
data = [(1,'张三',20,'男'),(2,'小红',18,'女')]

with open('userInfo.csv','w',encoding='gb18030',newline='') as fp: #这里是创建文件
    writer = csv.writer(fp)
    writer.writerow(title)
    writer.writerows(data)
    pass

with open('userInfo.csv','r',encoding='gb18030',newline='') as fp:
    reader = csv.reader(fp)#返回的是迭代器
    for i in reader:
        print(i)
    pass

#行读取
with open('userInfo.csv','r',encoding='gb18030',newline='') as fp:
    result = fp.readline()
    while result:
        print(result,end='')
        result = fp.readline()

#将csv文件读取为字典结构
with open('userInfo.csv','r',encoding='gb18030',newline='') as fp:
    dicts = csv.DictReader(fp)
    for line in dicts:
        print(dict(line),'*')

#将字典写入CSV
dicts = {'编号': '1', '姓名': '张三', '年龄': '20', '性别': '男'}
with open('userInfo1.csv','w',encoding='gb18030',newline='') as fp:
    dictW =csv.DictWriter(fp,fieldnames=dicts.keys())
    dictW.writeheader()
    dictW.writerow(dicts)

输出结果：

['编号', '姓名', '年龄', '性别']
['1', '张三', '20', '男']
['2', '小红', '18', '女']
编号,姓名,年龄,性别
1,张三,20,男
2,小红,18,女
{'编号': '1', '姓名': '张三', '年龄': '20', '性别': '男'} *
{'编号': '2', '姓名': '小红', '年龄': '18', '性别': '女'} *