python 字符串压缩算法_详解python用模块zlib压缩与解压字符串和文件的方法代码...

python中zlib模块是用来压缩或者解压缩数据，以便保存和传输。它是其他压缩工具的基础。下面来一起看看python用模块zlib压缩与解压字符串和文件的方法。话不多说，直接来看示例代码。

例子1：压缩与解压字符串import zlib

message = 'abcd1234'

compressed = zlib.compress(message)

decompressed = zlib.decompress(compressed)

print 'original:', repr(message)

print 'compressed:', repr(compressed)

print 'decompressed:', repr(decompressed)

结果original: 'abcd1234'

compressed: 'x\x9cKLJN1426\x01\x00\x0b\xf8\x02U'

decompressed: 'abcd1234'

例子2：压缩与解压文件import zlib

def compress(infile, dst, level=9):

infile = open(infile, 'rb')

dst = open(dst, 'wb')

compress = zlib.compressobj(level)

data = infile.read(1024)

while data:

dst.write(compress.compress(data))

data = infile.read(1024)

dst.write(compress.flush())

def decompress(infile, dst):

infile = open(infile, 'rb')

dst = open(dst, 'wb')

decompress = zlib.decompressobj()

data = infile.read(1024)

while data:

dst.write(decompress.decompress(data))

data = infile.read(1024)

dst.write(decompress.flush())

if __name__ == "__main__":

compress('in.txt', 'out.txt')

decompress('out.txt', 'out_decompress.txt')

结果

生成文件out_decompress.txt out.txt

问题――处理对象过大异常>>> import zlib

>>> a = '123'

>>> b = zlib.compress(a)

>>> b

'x\x9c342\x06\x00\x01-\x00\x97'

>>> a = 'a' * 1024 * 1024 * 1024 * 10

>>> b = zlib.compress(a)

Traceback (most recent call last):

File "", line 1, in

OverflowError: size does not fit in an int