【Python】Learn Python the hard way, ex17 文件复制

最新推荐文章于 2022-09-22 10:08:25 发布

原创最新推荐文章于 2022-09-22 10:08:25 发布 · 790 阅读

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本文介绍了一个使用Python实现的简单文件复制脚本，通过从命令行读取输入和输出文件名来完成文件内容的复制。文章展示了如何利用Python内置模块如sys和os.path来实现这一过程，并附带了测试结果。

from sys import argv
from os.path import exists

script, from_file, to_file = argv

print "Copying from %s to %s " % (from_file, to_file)

# we could do these two on one line too, how?
in_file = open(from_file)
indata = in_file.read()

print "The input file is %d bytes long" % len(indata)

print "Does the output file exist? %r" % exists(to_file)
print "Ready, hit RETURN to continue, CTRL-C to abort."
raw_input()

out_file = open(to_file, 'w')
out_file.write(indata)

print "Alright, all done."

out_file.close()
in_file.close()

'''
Test Result:

bogon:~ myRMBP$ python /Users/myRMBP/Desktop/ex17.py '/Users/myRMBP/Desktop/ex17_in_file.txt' '/Users/myRMBP/Desktop/ex17_out_file.txt'
Copying from /Users/myRMBP/Desktop/ex17_in_file.txt to /Users/myRMBP/Desktop/ex17_out_file.txt 
The input file is 21 bytes long
Does the output file exist? True
Ready, hit RETURN to continue, CTRL-C to abort.

Alright, all done.
'''

心得：

1， exists()函数不错

2，格式化字符串，引用时经常忘记变量前面的 %