How python compresses and extracts strings and files using module zlib

The zlib module in Python is used to compress or decompress data for storage and transmission. It is the basis for other compression tools. Let's take a look at Python's method of compressing and decompressing strings and files using module zlib. If you don't say more, just look at the sample code.

Example 1: compressing and decompressing strings

Importzlib Message= ' abcd1234 ' Compressed=zlib.compress (Message) Decompressed=zlib.decompress (compressed) print ' original: ', repr (message) print ' compressed: ', repr (compressed) print ' decompressed: ', repr (decompressed)

Results

Original: ' abcd1234 ' Compressed: ' X\X9CKLJN1426\X01\X00\X0B\XF8\X02U ' decompressed: ' abcd1234 '

Example 2: compressing and extracting files

Importzlib Defcompress (infile, DST, level=9): Infile=open (infile, ' RB ') Dst=open (DST, ' WB ') Compress=zlib.compressobj (Level) Data=infile.read (1024) Whiledata: Dst.write (compress.compress (data)) Data=infile.read (1024) Dst.write (Compress.flush ()) Defdecompress (infile, DST): Infile=open (infile, ' RB ') Dst=open (DST, ' WB ') Decompress=zlib.decompressobj () Data=infile.read (1024) Whiledata: 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 ')

Results

Generating files

Out_decompress.txt OUT.txt

Problem-handling object too large exception

>>>importzlib >>> 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 "<stdin>", line1,in<module> Overflowerror:size Doesnotfitinanint