Python 3.5 遍历字典列表

Question

我的密码是

index = 0
for key in dataList[index]:
    print(dataList[index][key])

似乎可以很好地打印索引 = 0 的字典键的值。

但是对于我的一生，我无法弄清楚如何将这个 for 循环放在一个 for 循环中，该循环遍历 dataList

中未知数量的字典

Answer 1

您可以轻松做到这一点：

for dict_item in dataList:
  for key in dict_item:
    print dict_item[key]

它将遍历列表，对于列表中的每个字典，它将遍历键并打印其值。

Answer 2

您可以迭代 list 的 len 的 range 的索引：

dataList = [{'a': 1}, {'b': 3}, {'c': 5}]
for index in range(len(dataList)):
    for key in dataList[index]:
        print(dataList[index][key])

或者您可以使用带有 index 计数器的 while 循环：

dataList = [{'a': 1}, {'b': 3}, {'c': 5}]
index = 0
while index < len(dataList):
    for key in dataList[index]:
        print(dataList[index][key])
    index += 1

您甚至可以直接遍历列表中的元素：

dataList = [{'a': 1}, {'b': 3}, {'c': 5}]
for dic in dataList:
    for key in dic:
        print(dic[key])

甚至可以不进行任何查找，只需遍历字典的值即可：

dataList = [{'a': 1}, {'b': 3}, {'c': 5}]
for dic in dataList:
    for val in dic.values():
        print(val)

或者将迭代包装在列表推导式或生成器中，稍后再解压它们：

dataList = [{'a': 1}, {'b': 3}, {'c': 5}]
print(*[val for dic in dataList for val in dic.values()], sep='\n')

可能性是无限的。喜欢什么是选择的问题。

Answer 3

use=[{'id': 29207858, 'isbn': '1632168146', 'isbn13': '9781632168146', 'ratings_count': 0}]
for dic in use:
    for val,cal in dic.items():
        print(f'{val} is {cal}')

Answer 4

def extract_fullnames_as_string(list_of_dictionaries):
    
return list(map(lambda e : "{} {}".format(e['first'],e['last']),list_of_dictionaries))


names = [{'first': 'Zhibekchach', 'last': 'Myrzaeva'}, {'first': 'Gulbara', 'last': 'Zholdoshova'}]
print(extract_fullnames_as_string(names))

#Well...the shortest way (1 line only) in Python to extract data from the list of dictionaries is using lambda form and map together.

Answer 5

"""提供最大灵活性并且似乎更适合我的方法如下："""

在名为....

的函数中遍历列表

def extract_fullnames_as_string(list_of_dictionaries):

    result = ([val for dic in list_of_dictionaries for val in 
    dic.values()])

    return ('My Dictionary List is ='result)


    dataList = [{'first': 3, 'last': 4}, {'first': 5, 'last': 7},{'first': 
    15, 'last': 9},{'first': 51, 'last': 71},{'first': 53, 'last': 79}]
    
    print(extract_fullnames_as_string(dataList))

"""这样，数据列表可以是你扔给它的任何格式的字典，否则你最终可能会处理格式问题，我发现。试试下面的方法，它仍然有效.... ..."""

    dataList1 = [{'a': 1}, {'b': 3}, {'c': 5}]
    dataList2 = [{'first': 'Zhibekchach', 'last': 'Myrzaeva'}, {'first': 
    'Gulbara', 'last': 'Zholdoshova'}]

    print(extract_fullnames_as_string(dataList1))
    print(extract_fullnames_as_string(dataList2))

Answer 6

另一个 pythonic 解决方案是使用 collections module.

这是一个例子，我想生成一个只包含 'Name' 和 'Last Name' 值的字典：

from collections import defaultdict

test_dict = [{'Name': 'Maria', 'Last Name': 'Bezerra', 'Age': 31},
             {'Name': 'Ana', 'Last Name': 'Mota', 'Age': 31},
             {'Name': 'Gabi', 'Last Name': 'Santana', 'Age': 31}]

collect = defaultdict(dict)

# at this moment, 'key' becomes every dict of your list of dict
for key in test_dict:
    collect[key['Name']] = key['Last Name']

print(dict(collect))

输出应该是：

{'Name': 'Maria', 'Last Name': 'Bezerra'}, {'Name': 'Ana', 'Last Name': 'Mota'}, {'Name': 'Gabi', 'Last Name': 'Santana'}

Answer 7

有一个类似的问题，通过使用单个 for 循环遍历列表来修复我的问题，请参见代码片段

de = {"file_name":"jon","creation_date":"12/05/2022","location":"phc","device":"s3","day":"1","time":"44692.5708703703","year":"1900","amount":"3000","entity":"male"}
se = {"file_name":"bone","creation_date":"13/05/2022","location":"gar","device":"iphone","day":"2","time":"44693.5708703703","year":"2022","amount":"3000","entity":"female"}
re = {"file_name":"cel","creation_date":"12/05/2022","location":"ben car","device":"galaxy","day":"1","time":"44695.5708703703","year":"2022","amount":"3000","entity":"male"}
te = {"file_name":"teiei","creation_date":"13/05/2022","location":"alcon","device":"BB","day":"2","time":"44697.5708703703","year":"2022","amount":"3000","entity":"female"}
ye = {"file_name":"js","creation_date":"12/05/2022","location":"woji","device":"Nokia","day":"1","time":"44699.5708703703","year":"2022","amount":"3000","entity":"male"}
ue = {"file_name":"jsdjd","creation_date":"13/05/2022","location":"town","device":"M4","day":"5","time":"44700.5708703703","year":"2022","amount":"3000","entity":"female"}


d_list = [de,se,re,te,ye,ue]


for dic in d_list:
    print (dic['file_name'],dic['creation_date'])

Python 3.5 遍历字典列表

Python 3.5 iterate through a list of dictionaries

python

dictionary

for-loop

list

python-3.5

在名为....