我想做的事情是:

foo = {
    'foo': 1,
    'zip': 2,
    'zam': 3,
    'bar': 4
}

if ("foo", "bar") in foo:
    #do stuff

我如何检查是否foo和酒吧都在dict foo?


当前回答

my_dict = {
    'name': 'Askavy',
    'country': 'India',
    'age': 30
}

if set(('name', 'country','age')).issubset(my_dict.keys()):
     print("All keys are present in the dictionary") 
else: 
    print("All keys are not present in  the dictionary") 

其他回答

这只是我的看法,在所有给定的选项中,有两个方法很容易理解。所以我的主要标准是代码可读性强,而不是特别快。为了保持代码的可理解性,我更喜欢给定的可能性:

var <=var2.keys() var.issubset(var2)

事实上,“var <= var2.keys()”在我下面的测试中执行得更快,我更喜欢这个。

import timeit

timeit.timeit('var <= var2.keys()', setup='var={"managed_ip", "hostname", "fqdn"}; var2= {"zone": "test-domain1.var23.com", "hostname": "bakje", "api_client_ip": "127.0.0.1", "request_data": "", "request_method": "GET", "request_url": "hvar2p://127.0.0.1:5000/test-domain1.var23.com/bakje", "utc_datetime": "04-Apr-2019 07:01:10", "fqdn": "bakje.test-domain1.var23.com"}; var={"managed_ip", "hostname", "fqdn"}')
0.1745898080000643

timeit.timeit('var.issubset(var2)', setup='var={"managed_ip", "hostname", "fqdn"}; var2= {"zone": "test-domain1.var23.com", "hostname": "bakje", "api_client_ip": "127.0.0.1", "request_data": "", "request_method": "GET", "request_url": "hvar2p://127.0.0.1:5000/test-domain1.var23.com/bakje", "utc_datetime": "04-Apr-2019 07:01:10", "fqdn": "bakje.test-domain1.var23.com"}; var={"managed_ip", "hostname", "fqdn"};')
0.2644960229999924
if {"foo", "bar"} <= myDict.keys(): ...

如果你还在使用python2,你可以这样做

if {"foo", "bar"} <= myDict.viewkeys(): ...

如果你仍然使用非常老的Python <= 2.6,你可以在字典上调用set,但它会遍历整个字典来构建集合,这是很慢的:

if set(("foo", "bar")) <= set(myDict): ...

短而甜

{"key1", "key2"} <= {*dict_name}

在确定是否只有一些键匹配的情况下,这是有效的:

any_keys_i_seek = ["key1", "key2", "key3"]

if set(my_dict).intersection(any_keys_i_seek):
    # code_here
    pass

还有另一个选项,如果只有一些键匹配:

any_keys_i_seek = ["key1", "key2", "key3"]

if any_keys_i_seek & my_dict.keys():
    # code_here
    pass

并不是说这不是你没有想过的事情,但我发现最简单的事情通常是最好的:

if ("foo" in foo) and ("bar" in foo):
    # do stuff