假设我有这个:
[
{"name": "Tom", "age": 10},
{"name": "Mark", "age": 5},
{"name": "Pam", "age": 7}
]
通过搜索“Pam”作为名称,我想检索相关的字典:{name:“Pam”,年龄:7}
如何做到这一点?
假设我有这个:
[
{"name": "Tom", "age": 10},
{"name": "Mark", "age": 5},
{"name": "Pam", "age": 7}
]
通过搜索“Pam”作为名称,我想检索相关的字典:{name:“Pam”,年龄:7}
如何做到这一点?
当前回答
为@FrédéricHamidi添加一点点。
如果你不确定字典列表中是否有键,这样做会有帮助:
next((item for item in dicts if item.get("name") and item["name"] == "Pam"), None)
其他回答
dicts=[
{"name": "Tom", "age": 10},
{"name": "Mark", "age": 5},
{"name": "Pam", "age": 7}
]
from collections import defaultdict
dicts_by_name=defaultdict(list)
for d in dicts:
dicts_by_name[d['name']]=d
print dicts_by_name['Tom']
#output
#>>>
#{'age': 10, 'name': 'Tom'}
这是在字典列表中搜索值的一般方法:
def search_dictionaries(key, value, list_of_dictionaries):
return [element for element in list_of_dictionaries if element[key] == value]
我会像这样创建一个字典的字典:
names = ["Tom", "Mark", "Pam"]
ages = [10, 5, 7]
my_d = {}
for i, j in zip(names, ages):
my_d[i] = {"name": i, "age": j}
或者,使用与问题中完全相同的信息:
info_list = [{"name": "Tom", "age": 10}, {"name": "Mark", "age": 5}, {"name": "Pam", "age": 7}]
my_d = {}
for d in info_list:
my_d[d["name"]] = d
然后你可以执行my_d["Pam"],得到{"name": "Pam", "age": 7}
你必须遍历列表中的所有元素。没有捷径!
除非在其他地方保存了一个包含指向列表项的名称的字典,但这时必须处理从列表中弹出元素的后果。
将接受的答案放在函数中,以便于重用
def get_item(collection, key, target):
return next((item for item in collection if item[key] == target), None)
也可以写成
get_item_lambda = lambda collection, key, target : next((item for item in collection if item[key] == target), None)
结果
key = "name"
target = "Pam"
print(get_item(target_list, key, target))
print(get_item_lambda(target_list, key, target))
#{'name': 'Pam', 'age': 7}
#{'name': 'Pam', 'age': 7}
如果键可能不在目标字典中,请使用dict。get和避免KeyError
def get_item(collection, key, target):
return next((item for item in collection if item.get(key, None) == target), None)
get_item_lambda = lambda collection, key, target : next((item for item in collection if item.get(key, None) == target), None)