python None、 空字符串 ‘‘、 0、 空对象(空字典 {})、 空数组[] 的布尔值(boolean)都为false_空字典{}布尔值

code:

def boolean_study():
    a = None
    b = ''
    c = 0
    d = {}
    e = []
    f = ()
    if a:
        print('i am None')
    elif b:
        print('i am empty str')
    elif c:
        print('i am 0')
    elif d:
        print('i am empty obj or empty dic')
    elif e:
        print('i am empty array or list')
    elif f:
        print('i am empty tuple')
    else:
        print('a, b, c, d, e and f is False')

boolean_study()
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

result:

a, b, c, d, e and f is False
1

举一反三: javascript、 typescript 也类似