python多线程

python多线程

需要用到threading库

1.一个简单的多线程

import threading,time

def run(n):
    print("thread",n)
    time.sleep(1)
    print("2s")
    time.sleep(1)
    print("1s")
    time.sleep(1)

def p_time(threadName,delay):
    count = 0
    while count < 5:
        time.sleep(delay)
        count += 1
        print("%s : %s"%(threadName,time.ctime(time.time())))
        
if __name__ == '__main__':
    # target指函数名，args是指函数所传得参数
    threading.Thread(target=run,args=("thread-1",)).start()
    threading.Thread(target=run,args=("thread-2",)).start()
    threading.Thread(target=p_time,args=("thread-3",1)).start()
    threading.Thread(target=p_time,args=("thread-4",1)).start()

2.自定义线程：继承threading.Thread来定义线程类，其本质是重构Thread类中的run方法

class MyThread(threading.Thread):

    def __init__(self,name):
        threading.Thread.__init__(self) # 重构run函数，必须写
        self.name = name

    def run(self):
        print("开始线程：{}".format(self.name))
        print(print_time(self.name,1))
        print("结束线程：{}".format(self.name))

def print_time(threadName,delay):
    count = 0
    while count < 5:
        time.sleep(delay)
        count += 1
        print("%s: %s" %
        (threadName,time.ctime(time.time())))


if __name__ == '__main__':
    # 创建线程
    t1 = MyThread("t1")
    t2 = MyThread("t2")
    # 开始线程
    t1.start()
    t2.start()