如何在Python中漂亮地打印深度为~4的字典?我尝试用pprint()进行漂亮的打印,但它不起作用:

import pprint 
pp = pprint.PrettyPrinter(indent=4)
pp.pprint(mydict)

我只是想要一个缩进(“\t”)为每个嵌套,这样我就会得到这样的东西:

key1
    value1
    value2
    key2
       value1
       value2

等。

我该怎么做呢?


当前回答

某物,我觉得很漂亮

def pretty(d, indent=0):
    for key, value in d.iteritems():
        if isinstance(value, dict):
            print '\t' * indent + (("%30s: {\n") % str(key).upper())
            pretty(value, indent+1)
            print '\t' * indent + ' ' * 32 + ('} # end of %s #\n' % str(key).upper())
        elif isinstance(value, list):
            for val in value:
                print '\t' * indent + (("%30s: [\n") % str(key).upper())
                pretty(val, indent+1)
                print '\t' * indent + ' ' * 32 + ('] # end of %s #\n' % str(key).upper())
        else:
            print '\t' * indent + (("%30s: %s") % (str(key).upper(),str(value)))

其他回答

我自己是一个相对的python新手,但过去几周我一直在使用嵌套字典,这就是我想到的。

你应该尝试使用堆栈。将根字典中的键变成一个列表的列表:

stack = [ root.keys() ]     # Result: [ [root keys] ]

按照从最后到第一个的相反顺序,查找字典中的每个键,看看它的值是否(也是)一个字典。如果不是,打印密钥,然后删除它。但是,如果键的值是一个字典,则打印该键,然后将该值的键附加到堆栈的末尾,并以相同的方式开始处理该列表,对每个新的键列表进行递归重复。

如果每个列表中第二个键的值是一个字典,那么在几轮之后,你会得到这样的结果:

[['key 1','key 2'],['key 2.1','key 2.2'],['key 2.2.1','key 2.2.2'],[`etc.`]]

这种方法的优点是缩进只是\t乘以堆栈的长度:

indent = "\t" * len(stack)

缺点是为了检查每个键,你需要散列到相关的子字典,尽管这可以通过列表理解和简单的for循环轻松处理:

path = [li[-1] for li in stack]
# The last key of every list of keys in the stack

sub = root
for p in path:
    sub = sub[p]


if type(sub) == dict:
    stack.append(sub.keys()) # And so on

注意,这种方法将要求清除尾随的空列表,并删除后跟空列表的任何列表中的最后一个键(当然,这可能会创建另一个空列表,等等)。

还有其他方法来实现这个方法,但希望这能给你一个基本的想法。

编辑:如果您不想进行所有这些操作,pprint模块将以良好的格式打印嵌套字典。

这里有一些东西可以打印任何类型的嵌套字典,同时跟踪“父”字典。

dicList = list()

def prettierPrint(dic, dicList):
count = 0
for key, value in dic.iteritems():
    count+=1
    if str(value) == 'OrderedDict()':
        value = None
    if not isinstance(value, dict):
        print str(key) + ": " + str(value)
        print str(key) + ' was found in the following path:',
        print dicList
        print '\n'
    elif isinstance(value, dict):
        dicList.append(key)
        prettierPrint(value, dicList)
    if dicList:
         if count == len(dic):
             dicList.pop()
             count = 0

prettierPrint(dicExample, dicList)

这是根据不同格式进行打印的一个很好的起点,就像op中指定的那样。你真正需要做的只是围绕打印块进行操作。注意,它将查看该值是否为'OrderedDict()'。这取决于你是否使用容器数据类型集合中的东西,你应该做这些故障保护,这样elif块不会因为它的名字而把它视为一个额外的字典。就像现在,一个例子字典

example_dict = {'key1': 'value1',
            'key2': 'value2',
            'key3': {'key3a': 'value3a'},
            'key4': {'key4a': {'key4aa': 'value4aa',
                               'key4ab': 'value4ab',
                               'key4ac': 'value4ac'},
                     'key4b': 'value4b'}

将打印

key3a: value3a
key3a was found in the following path: ['key3']

key2: value2
key2 was found in the following path: []

key1: value1
key1 was found in the following path: []

key4ab: value4ab
key4ab was found in the following path: ['key4', 'key4a']

key4ac: value4ac
key4ac was found in the following path: ['key4', 'key4a']

key4aa: value4aa
key4aa was found in the following path: ['key4', 'key4a']

key4b: value4b
key4b was found in the following path: ['key4']

~修改代码以适应问题的格式~

lastDict = list()
dicList = list()
def prettierPrint(dic, dicList):
    global lastDict
    count = 0
    for key, value in dic.iteritems():
        count+=1
        if str(value) == 'OrderedDict()':
            value = None
        if not isinstance(value, dict):
            if lastDict == dicList:
                sameParents = True
            else:
                sameParents = False

            if dicList and sameParents is not True:
                spacing = ' ' * len(str(dicList))
                print dicList
                print spacing,
                print str(value)

            if dicList and sameParents is True:
                print spacing,
                print str(value)
            lastDict = list(dicList)

        elif isinstance(value, dict):
            dicList.append(key)
            prettierPrint(value, dicList)

        if dicList:
             if count == len(dic):
                 dicList.pop()
                 count = 0

使用相同的示例代码,它将打印以下内容:

['key3']
         value3a
['key4', 'key4a']
                  value4ab
                  value4ac
                  value4aa
['key4']
         value4b

This isn't exactly what is requested in OP. The difference is that a parent^n is still printed, instead of being absent and replaced with white-space. To get to OP's format, you'll need to do something like the following: iteratively compare dicList with the lastDict. You can do this by making a new dictionary and copying dicList's content to it, checking if i in the copied dictionary is the same as i in lastDict, and -- if it is -- writing whitespace to that i position using the string multiplier function.

yapf的另一个选择:

from pprint import pformat
from yapf.yapflib.yapf_api import FormatCode

dict_example = {'1': '1', '2': '2', '3': [1, 2, 3, 4, 5], '4': {'1': '1', '2': '2', '3': [1, 2, 3, 4, 5]}}
dict_string = pformat(dict_example)
formatted_code, _ = FormatCode(dict_string)

print(formatted_code)

输出:

{
    '1': '1',
    '2': '2',
    '3': [1, 2, 3, 4, 5],
    '4': {
        '1': '1',
        '2': '2',
        '3': [1, 2, 3, 4, 5]
    }
}

我的第一个想法是JSON序列化器可能很擅长嵌套字典,所以我会欺骗并使用它:

>>> import json
>>> print(json.dumps({'a':2, 'b':{'x':3, 'y':{'t1': 4, 't2':5}}},
...                  sort_keys=True, indent=4))
{
    "a": 2,
    "b": {
        "x": 3,
        "y": {
            "t1": 4,
            "t2": 5
        }
    }
}

下面是我根据sth的注释写的函数。它的工作原理与json相同。转储与缩进,但我使用制表符而不是缩进的空间。在Python 3.2+中,您可以直接将缩进指定为'\t',但在2.7中不能。

def pretty_dict(d):
    def pretty(d, indent):
        for i, (key, value) in enumerate(d.iteritems()):
            if isinstance(value, dict):
                print '{0}"{1}": {{'.format( '\t' * indent, str(key))
                pretty(value, indent+1)
                if i == len(d)-1:
                    print '{0}}}'.format( '\t' * indent)
                else:
                    print '{0}}},'.format( '\t' * indent)
            else:
                if i == len(d)-1:
                    print '{0}"{1}": "{2}"'.format( '\t' * indent, str(key), value)
                else:
                    print '{0}"{1}": "{2}",'.format( '\t' * indent, str(key), value)
    print '{'
    pretty(d,indent=1)
    print '}'

Ex:

>>> dict_var = {'a':2, 'b':{'x':3, 'y':{'t1': 4, 't2':5}}}
>>> pretty_dict(dict_var)
{
    "a": "2",
    "b": {
        "y": {
            "t2": "5",
            "t1": "4"
        },
        "x": "3"
    }
}