Question

我有一个python字典如下

test={}
test['key1']={}
test['key1'] ['key2'] = {}
test['key1']['key2']['key3'] = 'val1'
test['key1']['key2']['key4'] = 'val2'

我有另一本词典如下

 check = {}
    check['key1']={}
    check['key1'] ['key2'] = {}
    check['key1']['key2']['key5'] = 'val3'
    check['key1']['key2']['key6'] = 'val4'

我想结合这个词典，所以我做了以下

test.update(check)

但如果我在尝试打印测试字典时执行此操作，则会打印

{'key1': {'key2': {'key5': 'val3', 'key6': 'val4'}}}

但预期输出

{'key1': {'key2': {'key3': 'val1', 'key4': 'val2','key5': 'val3', 'key6': 'val4'}}}

Answer 1

这是实现深度合并的一种方法：

test={}
test['key1']={}
test['key1'] ['key2'] = {}
test['key1']['key2']['key3'] = 'val1'
test['key1']['key2']['key4'] = 'val2'

check = {}
check['key1']={}
check['key1'] ['key2'] = {}
check['key1']['key2']['key5'] = 'val3'
check['key1']['key2']['key6'] = 'val4'

def deep_merge(a, b):
    for key, value in b.items():
        if isinstance(value, dict):
            # get node or create one
            node = a.setdefault(key, {})
            deep_merge(value, node)
        else:
            a[key] = value

    return a

deep_merge(test,check)
print(test)
# {'key1': {'key2': {'key3': 'val1', 'key6': 'val4', 'key5': 'val3', 'key4': 'val2'}}}

它会改变test并使check保持不变。

Answer 2

如果x和y是dicts，那么z = {**x, **y}是合并x和y的字典

Answer 3

要深度合并，需要使用：

def merge(source, destination):
    for key, value in source.items():
        if isinstance(value, dict):
            # get node or create one
            node = destination.setdefault(key, {})
            merge(value, node)
        else:
            destination[key] = value
    return destination

test = {'key1': {'key2': {'key3': 'val1', 'key4': 'val2'}}}
check = {'key1': {'key2': {'key6': 'val4', 'key5': 'val3'}}}

print(merge(test, check))
# {'key1': {'key2': {'key3': 'val1', 'key6': 'val4', 'key4': 'val2', 'key5': 'val3'}}}

来自vincent的Python deep merge dictionary data的代码

在python中组合两个dict

3 个答案: