本文實例講述了python讀寫二進制文件的方法。分享給大家供大家參考。具體如下：
初學python，現在要讀一個二進制文件，查找doc只發現 file提供了一個read和write函數，而且讀寫的都是字符串，如果只是讀寫char等一個字節的還行，要想讀寫如int,double等多字節數 據就不方便了。在網上查到一篇貼子，使用struct模塊里面的pack和unpack函數進行讀寫。下面就自己寫代碼驗證一下。
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>>> from struct import *>>> file = open(r"c:/debug.txt", "wb")>>> file.write(pack("idh", 12345, 67.89, 15))>>> file.close() |
接著再將其讀進來
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>>> 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,c12345 67.89 15>>> file.close() |
在操作過程中需要注意數據的size
注意 wb,rb中的b字，一定不可以少
方法1：
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myfile=open('c:\\t','rb')s=myfile.read(1)byte=ord(s) #將一個字節 讀成一個數print hex(byte) #轉換成16進制的字符串 |
方法2
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import structmyfile=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程序設計有所幫助。
