40 lines
1.2 KiB
Python
40 lines
1.2 KiB
Python
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from struct import Struct
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def write_records(records, format, f):
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# 创建一个结构体
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record_struct = Struct(format)
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# 将数组元素解包后打包放入文件
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for r in records:
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f.write(record_struct.pack(*r))
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# 简单来说，这是什么原理呢?
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# 就是我知道我结构体的格式是什么样的，然后我造一个相同的结构体，然后把数据按照结构大小分块读出来，然后重新解包
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# 本质就是结构体的pack和unpack
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def read_records(format, file):
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record_struct = Struct(format)
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# b''表示直到数据返回变成b''我们就收手
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chunks = iter(lambda: file.read(record_struct.size), b'')
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return (record_struct.unpack(chunk) for chunk in chunks)
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if __name__ == '__main__':
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records = [
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(1, 2.3, 4.5),
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(6, 7.8, 9.0),
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(12, 13.4, 56.7)
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]
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# 首先我们造一个二进制结构数组文件
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# with open('6.数据编码与处理/11.data.bin', 'wb') as f:
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# write_records(records, '<idd', f)
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with open('6.数据编码与处理/11.data.bin', 'rb') as f:
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for rec in read_records("<idd", f):
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print(rec)
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# 要进一步理解Struct，我们就要学习这个包的<idd是什么东西了
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