Python - 常用函数 - csv

我会带着你远行 2023-10-12 15:10 54阅读 0赞

## csv文件 ##

Name,Age,City
    lfsun,25,北京
    lfsun666,30,上海
    lfsun666666,35,广州

![在这里插入图片描述][a4cdb430f261458d88334afd50c46ed1.png]

## CSV文件简单读取 ##

import csv
    
    # 打开CSV文件
    with open('example.csv', 'r', encoding='utf-8') as file:
        # 创建CSV阅读器对象
        reader = csv.reader(file)
    
        # 逐行读取CSV数据
        for row in reader:
            # 打印每一行的数据
            print(row)

![在这里插入图片描述][b7f469c4ec8240d2a78ce9a2bfccde4e.png]

## 写入 ##

import csv
    
    # 学生数据
    students = [
        {
        'Name': 'lfsun', 'Grade': 85},
        {
        'Name': 'lfsun777', 'Grade': 92},
        {
        'Name': 'lfsun7777777', 'Grade': 78}
    ]
    
    # 写入CSV文件
    with open('grades.csv', 'w', newline='') as file:
        # 创建CSV写入器对象
        writer = csv.writer(file)
    
        # 写入表头
        writer.writerow(['Name', 'Grade'])
    
        # 逐行写入数据
        #for student in students:
            # writer.writerow([student['Name'], student['Grade']]) # 这样会导致最后一行为空的，是多的一行
        writer.writerows([[student['Name'], student['Grade']] for student in students])

![在这里插入图片描述][5f861d72860d49af88b3e444fe2e3491.png]

## 处理csv ##

import csv
    
    # 打开CSV文件
    with open('grades.csv', 'r', encoding='utf-8') as file:
        # 创建CSV阅读器对象
        reader = csv.reader(file)
    
        # 跳过表头
        next(reader)
    
        # 初始化变量
        total_grade = 0
        count = 0
    
        # 逐行处理数据
        for row in reader:
            # 提取分数并累加
            grade = int(row[1])
            total_grade += grade
            count += 1
    
        # 计算平均分数
        average_grade = total_grade / count
    
        # 打印结果
        print(f'Average Grade: {
          average_grade}')

[a4cdb430f261458d88334afd50c46ed1.png]: https://img-blog.csdnimg.cn/a4cdb430f261458d88334afd50c46ed1.png
[b7f469c4ec8240d2a78ce9a2bfccde4e.png]: https://img-blog.csdnimg.cn/b7f469c4ec8240d2a78ce9a2bfccde4e.png
[5f861d72860d49af88b3e444fe2e3491.png]: https://img-blog.csdnimg.cn/5f861d72860d49af88b3e444fe2e3491.png