使用 JSON 保存 Python 元组

发布于03月31日

我对这一点还是有点陌生，所以我可能不知道事物的所有常规术语:

Is it possible to preserve Python tuples when encoding with JSON? Right now json.loads(json.dumps(tuple)) gives me a list back. I don't want to convert my tuples to lists, but I want to use JSON. So, are there options?

原因是:

推荐答案

您可以编写高度特殊化的编码器和解码器挂钩:

import json

class MultiDimensionalArrayEncoder(json.JSONEncoder):
    def encode(self, obj):
        def hint_tuples(item):
            if isinstance(item, tuple):
                return {'__tuple__': True, 'items': item}
            if isinstance(item, list):
                return [hint_tuples(e) for e in item]
            if isinstance(item, dict):
                return {key: hint_tuples(value) for key, value in item.items()}
            else:
                return item

        return super(MultiDimensionalArrayEncoder, self).encode(hint_tuples(obj))

def hinted_tuple_hook(obj):
    if '__tuple__' in obj:
        return tuple(obj['items'])
    else:
        return obj


enc = MultiDimensionalArrayEncoder()
jsonstring =  enc.encode([1, 2, (3, 4), [5, 6, (7, 8)]])

print jsonstring

# [1, 2, {"items": [3, 4], "__tuple__": true}, [5, 6, {"items": [7, 8], "__tuple__": true}]]

print json.loads(jsonstring, object_hook=hinted_tuple_hook)

# [1, 2, (3, 4), [5, 6, (7, 8)]]