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python3 with opEn

try: with open("path/to/filename.file", "r") as f: pass # do with file handleexcept Exception as e: print(e) # do with exception

利用with来打开文件,会在系统觉得其不用时自动关闭,不用手动调用close()方法关闭

Python文档中有提到: open('eggs.csv', newline='') 也就是说,打开文件的时候多指定一个参数。Python文档中也有这样的示例: import csvwith open('eggs.csv', 'w', newline='') as csvfile: spamwriter = csv.writer(csvfile, delimiter=' ',...

with open("test.txt") as file: data = file.read()

with open(r"C:\Users\*******\Desktop\pokemon.csv") as f:少了个r

ex5.py文件的第二行: script, filename = argv 这句是什么意思? 而你的命令行: python ex5.py 3.txt 提供了多少个参数?

with open('文件路径') as f: print(f.read())with open('文件路径', 'w') as f: f.write('写的内容')

with open('abc.txt','r') as f: balabalabala 等价于 try: f = open('abc.txt','r') except: pass else: balabalabala finally: f.close() 语法是不是简洁多了?

写在引号中的才表示原始文字 data_load("jame.txt") 如果直接写就会当成变量处理,并没有定义变量james,因此提示变量未定义

open函数中的文件名默认是寻找当前目录下的这个文件 如果当前目录下没有就会报错。建议在日常使用中写上绝对路径(完整路径) # -*- encoding:utf-8 -*-with open('a.txt') as f: res = f.readline() print(res)当前目录下没有a.txt 下面是报错 ...

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