python操作csv

直接上代码

import csv


def read_csv_demo1():
    with open('stock.csv', 'r') as f:
        # reader是一个迭代器
        reader = csv.reader(f)
        next(reader)  # 选出第一行
        for i in reader:
            name = i[3]
            volumn = i[-1]
            print({'name': name, 'volumn': volumn})


def read_csv_demo2():
    with open('stock.csv', 'r') as f:
        # 使用DictReader创建的reader对象
        # 不会包含标题那行的数据
        # reader 是一个迭代器,遍历这个迭代器,返回来的是一个字典
        reader = csv.DictReader(f)
        for i in reader:
            value = {'name': i['secShortName'], 'voluma': i['turnoverVol']}
            print(value)


def write_csv_demo1():
    headers = ['username', 'age', 'height']
    values = [
        ('张三', 18, 181),
        ('李四', 19, 190),
        ('王五', 20, 170)
    ]

    with open('classroom.csv', 'w', encoding='utf-8', newline='') as f:
        writer = csv.writer(f)
        writer.writerow(headers)  # 一行一行的写
        writer.writerows(values)  # 多行写入


def write_csv_demo2():
    headers = ['username', 'age', 'height']
    values = [
        {'username': '张三', 'age': 18, 'height': 180},
        {'username': '李四', 'age': 19, 'height': 190},
        {'username': '王五', 'age': 17, 'height': 170},
    ]
    with open('classroom1.csv', 'w', encoding='utf-8', newline='') as f:
        writer = csv.DictWriter(f, headers)  # 以字典形式写入,并传入表头
        # 写入表头数据的时候,需要调用writeheader方法
        writer.writeheader()
        writer.writerows(values)


if __name__ == '__main__':
    read_csv_demo1()
    read_csv_demo2()
    write_csv_demo1()
    write_csv_demo2()