Python学习总结 基础篇 函数

函数

使用关键字def来告诉Python你要定义一个函数。这是函数定义，向Python指出了函数名，还可能在括号内指出函数为完成其任务需要什么样的信息。
最简单的函数示例

def outprint():
    print("Hello World")
outprint()

传参函数

name = input("请输入一个名字")
def outprint(name):
    print("Hello , I'm " + name)
outprint(name)

name = input("请输入一个名字：")
def outprint(name):
    print("Hello , I'm " + name)
outprint(name)

name = input("请输入您的姓名:")
age = input("年龄：")
sex = input("性别：")
def introduce(name,age,sex):
    print(" My name is " + name)
    print(" I am " + age + " years old now!")
    print(" and I am a " + sex)
introduce(name,age ,sex)

关键字传参

name = input("请输入您的姓名:")
age = input("年龄：")
sex = input("性别：")
def introduce(userName,userAge,userSex):
    print(" My name is " + name)
    print(" I am " + age + " years old now!")
    print(" and I am a " + sex)
introduce(userName = name,userAge = age , userSex = sex)
introduce(userAge = age , userName = name, userSex = sex)
introduce( userSex = sex, userName = name, userAge = age)

可见用关键字的方式调用函数可以不用考虑参数的顺序，示例代码中三种不同的调用结果都相同。

设定参数默认值

name = input("请输入您的姓名:")
def introduce(name,age = "18",sex = 'boy'):
    print(" My name is " + name)
    print(" I am " + age + " years old now!")
    print(" and I am a " + sex)
introduce(name)

带有返回值

def sum(a,b):
    return a+b
res = sum(10,23)
print(res)