擅长:python、mysql、java
<p><code>struct.unpack</code>中没有这样的功能,但是可以定义这样一个函数:</p>
<pre><code>import struct
def unpack(fmt, astr):
"""
Return struct.unpack(fmt, astr) with the optional single * in fmt replaced with
the appropriate number, given the length of astr.
"""
# http://stackoverflow.com/a/7867892/190597
try:
return struct.unpack(fmt, astr)
except struct.error:
flen = struct.calcsize(fmt.replace('*', ''))
alen = len(astr)
idx = fmt.find('*')
before_char = fmt[idx-1]
n = (alen-flen)/struct.calcsize(before_char)+1
fmt = ''.join((fmt[:idx-1], str(n), before_char, fmt[idx+1:]))
return struct.unpack(fmt, astr)
print(unpack('b*','abc'))
# (97, 98, 99)
</code></pre>