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
注：
zlib.compress用于压缩流数据。参数string指定了要压缩的数据流，参数level指定了压缩的级别，它的取值范围是1到9。压缩速度与压缩率成反比，1表示压缩速度最快，而压缩率最低，而9则表示压缩速度最慢但压缩率最高
问题——处理对象过大异常
>>> import zlib
>>> a = ''
>>> b = zlib.compress(a)
>>> b
'x\x9c342\x06\x00\x01-\x00\x97'
>>> a = 'a' * * * *
>>> b = zlib.compress(a)
Traceback (most recent call last):
File "<stdin>", line , in <module>
OverflowError: size does not fit in an int