将嵌套字典转换为字符串

Question

我正在努力实现以下目标：

Input = {
    'key1':{'key11':'val11', 'key12':'val12'},
    'key2':{'key21':{'key211':'val211', 'key212':'val212'}},
    'key3':'val3',
    'key4':{'key41':'val41', 'key42':'val42'}
}

输出=

1）如果value是字典，则创建一个输出字符串变量=

^{pr2}$

2）如果值不是字典，则打印"just a string element"

以下是我的代码：

from collections import defaultdict

def stringBuilder(dictionary):
    stringOption = ""
    innerString = ""
    # print dictionary
    for key, value in dictionary.iteritems():
        if isinstance(value, dict):
            stringBuilder(value)
        else:
            innerString = innerString + " " + str(key) + " " + str(value)
            print innerString
            stringOption = "{" + innerString + " }"
            print stringOption
    return stringOption

d = {'key1':{'key11':'val11', 'key12':'val12'}, 'key2':{'key21':{'key211':'val211', 'key212':'val212'}}, 'key3':'val3', 'key4':{'key41':'val41', 'key42':'val42'}}
print d
stringOption = ""
for key, value in d.iteritems():
    if isinstance(value, dict):
        stringOption = stringOption + " " + str(key) + " " + stringBuilder(value)
        print stringOption
    else:
        print "just a string element"
print stringOption

以下是我得到的输出：

{'key2': {'key21': {'key211': 'val211', 'key212': 'val212'}}}
 key211 val211
{ key211 val211 }
 key2 
 key2 

Answer 1

一个伟大的递归练习！在

def rec(x):
    # assuming values are either str or otherwise dict
    if isinstance(x, str):
        return x
    return '{' + ' '.join([k + ' ' + rec(v) for (k, v) in x.items()]) + '}'


Input = {
    'key1':{'key11':'val11', 'key12':'val12'},
    'key2':{'key21':{'key211':'val211', 'key212':'val212'}},
    'key3':'val3',
    'key4':{'key41':'val41', 'key42':'val42'}
}

输出：

^{pr2}$

Answer 2

与其编写自己的实现（除非这是您想要的），为什么不使用json library？您可以扩展JSONEncoder和jsondeconder以适合您的用例吗？在

Answer 3

您的主要问题是您丢弃了dict案例的返回字符串：

    if isinstance(value, dict):
        stringBuilder(value)

相反，请尝试保存该值以向上传递：

^{pr2}$

结果输出：

key2 { key211 val211 key212 val212 } key1 { key12 val12 key11 val11 } key4 { key41 val41 key42 val42 }