Python - 如何更新多维字典

Question

跟进我之前的问题:Python - How to recursively add a folder's content in a dict .

当我为每个文件和文件夹构建信息字典时，我需要将它合并到主树字典中。到目前为止我发现的唯一方法是将 dict 写成文本字符串并将其解释为 dict 对象然后合并它。问题是根对象总是相同的，所以它被新的字典覆盖，我丢失了内容。

def recurseItem(Files, Item):
    global Settings
    ROOT = Settings['path']
    dbg(70, "Scanning " + Item)
    indices = path2indice(Item)
    ItemAnalysis = Analyse(Item)
    Treedict = ""#{'" + ROOT + "': "
    i=0
    for indice in indices:
        Treedict = Treedict + "{'" + indice + "': "
        i=i+1
    Treedict = Treedict + repr(ItemAnalysis)
    while i>0:
        Treedict = Treedict + "}"
        i=i-1
    Files = dict(Files.items() + Treedict.items())
return Files

有没有办法避免无法即时生成的困惑索引构造(即 Files[ROOT][fileName][fileName2][fileName3][fileName4] )？我需要能够在不覆盖根 key 的情况下更新 key 的内容。任何想法都会受到欢迎!

Answer 1

当然，您可以即时创建嵌套字典。这个怎么样:

# Example path, I guess something like this is produced by path2indice?!
indices = ("home", "username", "Desktop")

tree = {}

d = tree
for indice in indices[:-1]:
    if indice not in d:
        d[indice] = {}

    d = d[indice]

d[indices[-1]] = "some value"

print tree # this will print {'home': {'username': {'Desktop': 'some value'}}}