Python将byte数组转换为int，pythonbyte数组int,代码import str

Python将byte数组转换为int，pythonbyte数组int,代码import str

代码

import structimport ctypesdef test_struct(buf, offset):    return struct.unpack_from("I", buf, offset)[0]def test_ctypes(buf, offset):    return ctypes.c_uint32.from_buffer(buf, offset).valuedef test_multi(buf, offset):    return buf[offset] + (buf[offset+1] << 8) + (buf[offset+2] << 16) +(buf[offset+3] << 24)buf_w = bytearray(5)buf_w[1] = 1buf_r = buffer(buf_w)if __name__ == '__main__':    import timeit    t1 = timeit.Timer("test_struct(buf_r, 1)",                   "from __main__ import test_struct, buf_r")    t2 = timeit.Timer("test_ctypes(buf_w, 1)",                   "from __main__ import test_ctypes, buf_w")    t3 = timeit.Timer("test_multi(buf_w, 1)",                   "from __main__ import test_multi, buf_w")    print t1.timeit(number=1000)    print t2.timeit(number=1000)    print t3.timeit(number=1000)

结果

number = 100000.00819587707520.0125491619110.0112121105194number = 10000.000873088836670.001257896423340.00110197067261number = 1000.0000917911529541     # 9.17911529541e-050.0001339912414550.00011420249939number = 101.69277191162e-052.19345092773e-051.69277191162e-05number = 11.00135803223e-051.00135803223e-055.96046447754e-06