py对csv文件增删改查的代码

以下是Python中对CSV文件进行增删改查的示例代码：

1. 创建/打开CSV文件

import csv

# 打开或创建一个CSV文件
with open('test.csv', 'w', encoding='utf-8') as f:
    writer = csv.writer(f)
    # csv文件头部写入数据
    writer.writerow(['姓名', '年龄', '性别', '职业'])

2. 写入CSV文件数据

import csv

# 打开CSV文件
with open('test.csv', 'a', encoding='utf-8') as f:
    writer = csv.writer(f)
    # 写入一行数据
    writer.writerow(['Tom', '18', '男', '学生'])
    writer.writerow(['Lucy', '22', '女', '程序员'])

3. 读取CSV文件数据

import csv

# 打开CSV文件
with open('test.csv', 'r', encoding='utf-8') as f:
    reader = csv.reader(f)
    for row in reader:
        print(row)

4. 修改CSV文件数据

import csv

# 打开CSV文件
with open('test.csv', 'r', encoding='utf-8') as f:
    rows = []
    reader = csv.reader(f)
    for row in reader:
        if row[0] == 'Tom':  # 过滤出要修改的行
            row[1] = '20'  # 修改第2列
        rows.append(row)

# 写入修改后的数据到CSV文件
with open('test.csv', 'w', encoding='utf-8') as f:
    writer = csv.writer(f)
    for row in rows:
        writer.writerow(row)

5. 删除CSV文件数据

import csv

# 打开CSV文件
with open('test.csv', 'r', encoding='utf-8') as f:
    rows = []
    reader = csv.reader(f)
    for row in reader:
        if row[0] != 'Tom':  # 过滤出要删除的行
            rows.append(row)

# 写入删除后的数据到CSV文件
with open('test.csv', 'w', encoding='utf-8') as f:
    writer = csv.writer(f)
    for row in rows:
        writer.writerow(row)

以上是对CSV文件进行增删改查的Python示例代码，供参考。