Python包内引用非Python文件触发FileNotFoundError如何解决？

你使用的是相对于当前工作目录的相对路径，当你从项目根目录运行main.py时，Python的工作目录是main.py所在的根目录，相对路径dataFiles/brands.txt会被解析为[根目录]/dataFiles/brands.txt，但文件实际存放在SuperMarket包目录下，因此触发文件不存在报错。

通过当前Python文件的内置变量__file__定位目标文件的绝对路径，步骤如下：

• 第一步：在brands.py文件开头导入依赖模块

import os
import csv # 若原有代码已经导入csv可忽略这行

• 第二步：修改文件打开的路径拼接逻辑，修改后的完整代码如下：

class Brands:
    def getBrandsData(self, b_id=False, name=False):
        """:returns a list containing all brand data based on parameters"""
        data = []
        # 计算brands.txt的绝对路径
        current_dir = os.path.dirname(os.path.abspath(__file__))
        brands_file_path = os.path.join(current_dir, 'dataFiles', 'brands.txt')
        with open(brands_file_path, 'r') as file:
            reader = csv.reader(file, delimiter='|')
            for row in reader:
                subData = []
                if b_id:
                    subData.append(row[0])
                if name:
                    subData.append(row[1])
                data.append(subData)
        if [b_id, name].count(True) == 1:
            data = [item for sublist in data for item in sublist]
        return data

使用pathlib模块实现更简洁的路径拼接：

from pathlib import Path
import csv

class Brands:
    def getBrandsData(self, b_id=False, name=False):
        """:returns a list containing all brand data based on parameters"""
        data = []
        brands_file_path = Path(__file__).parent / 'dataFiles' / 'brands.txt'
        with open(brands_file_path, 'r') as file:
            reader = csv.reader(file, delimiter='|')
            for row in reader:
                subData = []
                if b_id:
                    subData.append(row[0])
                if name:
                    subData.append(row[1])
                data.append(subData)
        if [b_id, name].count(True) == 1:
            data = [item for sublist in data for item in sublist]
        return data

内容的提问来源于stack exchange，提问作者SARIN ALEXANDER