python——创建多线程

import time
import threading
def sing():
    for i in range(0,5):
        print("正在唱歌")
        time.sleep(1)

def dance():
    for i in range(0,5):
        print("正在跳舞")
        time.sleep(1)

def main():
    #create a thread
    t1=threading.Thread(target=sing)
    t2=threading.Thread(target=dance)
    t1.start()
    t2.start()
    #打印线程名字
    print(threading.enumerate())

if __name__ == "__main__":
    main()

import time
import threading
def sing():
    for i in range(0,5):
        print("正在唱歌")
        # time.sleep(1)

def dance():
    for i in range(0,5):
        print("正在跳舞")
        # time.sleep(1)
def eat():
    print("eat......")

def main():
    for i in range(5):
        t=threading.Thread(target=eat)
        t.start()

if __name__ == "__main__":
    main()

import threading
import time
class MyThread(threading.Thread):
    #必须要有run方法
    def run(self):#这个函数的名字必须是run
        for i in range(3):
            time.sleep(3)
            msg = "haha"
            print(msg)

if __name__ == "__main__":
    t=MyThread()
    t.start()#他会自动的去找run函数里面的方法，run函数的名字是固定的
    #没有定义start方法，却可以用，因为start是继承Thread类的方法，调用了start的方法之后会自动执行run方法