python中zip和unzip数据的方法_Python

python中zip和unzip数据的方法

2020-07-08 10:35依山带水 Python

这篇文章主要介绍了python中zip和unzip数据的方法,实例分析了Python中zlib模块的相关使用技巧,需要的朋友可以参考下

本文实例讲述了python zip和unzip数据的方法。分享给大家供大家参考。具体实现方法如下：

									# zipping and unzipping a string using the zlib module

									# a very large string could be zipped and saved to a file speeding up file writing time 

									# and later reloaded and unzipped by another program speeding up reading of the file

									# tested with Python24   vegaseat   15aug2005

									import zlib

									str1 = \

									"""Dallas Cowboys football practice at Valley Ranch was delayed on Wednesday 

									for nearly two hours. One of the players, while on his way to the locker

									room happened to look down and notice a suspicious looking, unknown white

									powdery substance on the practice field.

									The coaching staff immediately suspended practice while the FBI was

									called in to investigate. After a complete field analysis, the FBI

									determined that the white substance unknown to the players was the goal

									line.

									Practice was resumed when FBI Special Agents decided that the team would not

									be likely to encounter the substance again.

									"""

									print '-'*70 # 70 dashes for the fun of it

									print str1

									print '-'*70

									crc_check1 = zlib.crc32(str1)

									print "crc before zip=", crc_check1

									print "Length of original str1 =", len(str1)

									# zip compress the string

									zstr1 = zlib.compress(str1)

									print "Length of zipped str1 =", len(zstr1)

									filename = 'Dallas.zap'

									# write the zipped string to a file

									fout = open(filename, 'w')

									try:

									  print >> fout, zstr1

									except IOError:

									  print "Failed to open file..."

									else:

									  print "done writing", filename

									fout.close()

									# read the zip file back

									fin = open(filename, 'r')

									try:

									  zstr2 = fin.read()

									except IOError:

									  print "Failed to open file..."

									else:

									  print "done reading", filename

									fin.close()

									# unzip the zipped string from the file

									str2 = zlib.decompress(zstr2)

									print '-'*70

									print str2

									print '-'*70

									crc_check2 = zlib.crc32(str2)

									print "crc after unzip =", crc_check2, "(check sums should match)"