python *与**

Posted 2020-11-08 小宇先森

python中，在形参前面加上“*”与“”“**”，称为动态参数

加“*”时，函数可接受任意多个参数，全部放入一个元祖中

def F(*args):
    print(args)

F(123,"456")

# (123, ‘456‘)

加“**”时，函数接受参数时，返回为字典，需要写为如下形式：

def F(**kwargs):
    print(kwargs)

F(k1=123,k2="456")

# {‘k1‘: 123, ‘k2‘: ‘456‘}

 

def F(p,*args,**kwargs):
    print(p)
    print(args)
    print(kwargs)

F(11,"abc",[789],k1=123,k2="456")

# 11
# (‘abc‘, [789])
# {‘k1‘: 123, ‘k2‘: ‘456‘}

 

def F(*args):
    print(args)

li = [11,22,33,44]
F(li)
F(*li)

# ([11, 22, 33, 44],)
# (11, 22, 33, 44)

 

def F(**kwargs):
    print(kwargs)

li = {"k1":1,"k2":2}
F(k=li)
F(**li)

# {‘k‘: {‘k2‘: 2, ‘k1‘: 1}}
# {‘k2‘: 2, ‘k1‘: 1}