本文實例講述了python讀寫二進(jìn)制文件的方法。分享給大家供大家參考。具體如下：

初學(xué)python，現(xiàn)在要讀一個二進(jìn)制文件，查找doc只發(fā)現(xiàn) file提供了一個read和write函數(shù)，而且讀寫的都是字符串，如果只是讀寫char等一個字節(jié)的還行，要想讀寫如int,double等多字節(jié)數(shù) 據(jù)就不方便了。在網(wǎng)上查到一篇貼子，使用struct模塊里面的pack和unpack函數(shù)進(jìn)行讀寫。下面就自己寫代碼驗證一下。

>>> from struct import *
>>> file = open(r"c:/debug.txt", "wb")
>>> file.write(pack("idh", 12345, 67.89, 15))
>>> file.close()

接著再將其讀進(jìn)來

>>> file = open(r"c:/debug.txt", "rb")
>>> (a,b,c) = unpack("idh",file.read(8+8+2))
>>> a,b,c
(12345, 67.890000000000001, 15)
>>> print a,b,c
12345 67.89 15
>>> file.close()

在操作過程中需要注意數(shù)據(jù)的size

注意  wb,rb中的b字，一定不可以少

方法1：

myfile=open('c:\\t','rb')
s=myfile.read(1)
byte=ord(s) #將一個字節(jié) 讀成一個數(shù)
print hex(byte) #轉(zhuǎn)換成16進(jìn)制的字符串

方法2

import struct
myfile=open('c:\\t','rb').read(1)
print struct.unpack('c',myfile)
print struct.unpack('b',myfile)

寫入

To open a file for binary writing is easy, it is the same way you do for reading, just change the mode into “wb”.
file = open("test.bin","wb")
But, how to write the binary byte into the file?
You may write it straight away with hex code like this:
file.write("\x5F\x9D\x3E") file.close()
Now, check it out with hexedit,
hexedit test.bin
You will see this:
00000000 5F 9D 3E _.> 00000020 00000040
Now, open the file to append more bytes:
file = open("test.bin","ab")
What if I want to store by bin value into a stream and write it one short?
s ="\x45\xF3" s = s + "%c%c" % (0x45,0xF3) file.write(s) file.close()
Any convenient ways if I can obtained a hex string, and want to convert it back to binary format?
Yes, you just need to import binascii
import binascii hs="5B7F888489FEDA" hb=binascii.a2b_hex(hs) file.write(hb) file.close()

希望本文所述對大家的Python程序設(shè)計有所幫助。

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