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 zlibmessage = '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�KLJN1426�U'decompressed: 'abcd1234'
例子2:压缩与解压文件
import zlibdef 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�342-�'>>> a = 'a' * 1024 * 1024 * 1024 * 10>>> b = zlib.compress(a)Traceback (most recent call last): File "<stdin>", line 1, in <module>OverflowError: size does not fit in an int