公司网站设计素材,淘宝官网首页,做国外销售都上什么网站,互联网公司排名2005一、多线程#xff08;主线程和子线程同时执行#xff09;
1、主线程是程序本身#xff0c;看不到的,主线程和子线程没有依赖关系#xff0c;同步执行的#xff0c;若主线程先执行完#xff0c;会等子线程执行完毕#xff0c;程序结束
2、启动一个线程就是把一个函数传…
一、多线程主线程和子线程同时执行
1、主线程是程序本身看不到的,主线程和子线程没有依赖关系同步执行的若主线程先执行完会等子线程执行完毕程序结束
2、启动一个线程就是把一个函数传入并创建Thread实例然后调用start()开始执行run
3、threading.currentThread(): 返回当前的线程变量Thread(Thread-1, started 8056)、_MainThread(MainThread, started 14400)
threading.enumerate(): 返回一个包含正在运行的线程的list。正在运行指线程启动后、结束前不包括启动前和终止后的线程
threading.activeCount(): 返回正在运行的线程数量与len(threading.enumerate())有相同的结果
run(): 用以表示线程活动的方法
start():启动线程活动
join(timeout): 等待至线程中止。这阻塞调用线程直至线程的join() 方法被调用中止-正常退出或者抛出未处理的异常-或者是可选的超时发生
sAlive(): 返回线程是否活动的
getName(): 返回线程名setName(): 设置线程名
4、多线程实例
#函数式多线程
import time,threading
def learnEnglish():print(%s 橙子在学习英语 %s%(threading.currentThread(),time.ctime()))
def learnPython(name):print(%s %s在学习英语 %s%(threading.currentThread(),name,time.ctime()))
def learnC(name,course):print(%s %s在学习%s %s%(threading.currentThread(),name,course,time.ctime()))
start_timetime.time()
threads[]# 创建线程数组
thread1threading.Thread(targetlearnEnglish)#创建线程
thread2threading.Thread(targetlearnPython,args(橙汁,))
thread3threading.Thread(targetlearnC,args(柠檬,C,))
thread4threading.Thread(targetlearnC,kwargs{name:王荔,course:测试})
threads.append(thread1)#将线程1添加到线程数组
threads.append(thread2)
threads.append(thread3)
threads.append(thread4)
for i in threads:i.start()#启动线程
run_times(time.time()-start_time)
print(%s %s%(threading.currentThread(),time.ctime()))
print(主线程和子线程运行时间共%s%run_times)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
Thread(Thread-1, started 5664) 橙子在学习英语 Thu Mar 14 13:12:25 2019
Thread(Thread-2, started 6964) 橙汁在学习英语 Thu Mar 14 13:12:25 2019
Thread(Thread-3, started 17908) 柠檬在学习C Thu Mar 14 13:12:25 2019
Thread(Thread-4, started 17816) 王荔在学习测试 Thu Mar 14 13:12:25 2019
_MainThread(MainThread, started 12276) Thu Mar 14 13:12:25 2019
主线程和子线程运行时间共0.0009965896606445312Process finished with exit code 0
#多线程threading之封装
import threading,time
class MyThread(threading.Thread):#继承父类threading.Threaddef __init__(self,name,people):重写threading.Thread初始化内容super(MyThread,self).__init__()self.threadNamenameself.peoplepeopledef run(self):# 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数print(开始线程%s %s%(self.threadName,time.ctime()))print(结束线程%s %s%(self.threadName,time.ctime()))
start_timetime.time()
print(开始主线程%s%time.ctime())
thread1MyThread(Thread-1,王荔)
thread2MyThread(Thread-2,橙子)
thread1.start()
thread2.start()
print(退出主线程%s%time.ctime())
run_times(time.time()-start_time)
print(运行时间%s%run_times)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
开始主线程Thu Mar 14 13:16:10 2019
开始线程Thread-1 Thu Mar 14 13:16:10 2019
结束线程Thread-1 Thu Mar 14 13:16:10 2019
开始线程Thread-2 Thu Mar 14 13:16:10 2019
退出主线程Thu Mar 14 13:16:10 2019
运行时间0.0009996891021728516
结束线程Thread-2 Thu Mar 14 13:16:10 2019Process finished with exit code 0-----可以看到主线程和子线程是同时运行的主线程运行完子线程可能还在运行子线程运行完主线程可能还在运行 二、多线程之线程阻塞子线程.join()设置在start之后等所有阻塞线程运行完再运行主线程
1、阻塞主线程必须在start()方法后执行t1.join()等线程1运行完t2.join()等线程2运行完再运行主线程
2、如果想让主线程等待子线程结束后再运行就需用到【子线程.join()】,此方法是在start后与setDaemon相反
3、join(timeout)此方法有个timeout参数是线程超时时间设置
4、阻塞线程和非阻塞线程实例
#非阻塞线程主线程休眠1s子线程休眠3s
时间未统计到子线程只统计到主线程的说明主线程和子线程是同步执行的且主线程执行完了子线程还在执行import threading,time
class MyThread(threading.Thread):#继承父类threading.Threaddef __init__(self,name,people):重写threading.Thread初始化内容super(MyThread,self).__init__()self.threadNamenameself.peoplepeopledef run(self):# 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数print(开始线程%s %s%(self.threadName,time.ctime()))time.sleep(3)print(结束线程%s %s%(self.threadName,time.ctime()))
start_timetime.time()
print(开始主线程%s%time.ctime())
thread1MyThread(Thread-1,王荔)
thread2MyThread(Thread-2,橙子)
thread1.start()
thread2.start()
#thread1.join()
#thread2.join()
print(退出主线程%s%time.ctime())
time.sleep(1)
run_times(time.time()-start_time)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
开始主线程Thu Mar 14 13:30:07 2019
开始线程Thread-1 Thu Mar 14 13:30:07 2019
开始线程Thread-2 Thu Mar 14 13:30:07 2019
退出主线程Thu Mar 14 13:30:07 2019
运行时间1.0023198127746582
结束线程Thread-1 Thu Mar 14 13:30:10 2019
结束线程Thread-2 Thu Mar 14 13:30:10 2019Process finished with exit code 0
#阻塞线程1、阻塞线程2主线程休眠1s线程1和线程2休眠3s
主线程会等线程1和线程2执行完才会继续执行主线程统计时间为主线程1s子线程3s4s
import threading,time
class MyThread(threading.Thread):#继承父类threading.Threaddef __init__(self,name,people):重写threading.Thread初始化内容super(MyThread,self).__init__()self.threadNamenameself.peoplepeopledef run(self):# 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数print(开始线程%s %s%(self.threadName,time.ctime()))time.sleep(3)print(结束线程%s %s%(self.threadName,time.ctime()))
start_timetime.time()
print(开始主线程%s%time.ctime())
thread1MyThread(Thread-1,王荔)
thread2MyThread(Thread-2,橙子)
thread1.start()
thread2.start()
thread1.join()#阻塞线程1
thread2.join()#阻塞线程2
time.sleep(1)
print(退出主线程%s%time.ctime())
run_times(time.time()-start_time)
print(运行时间%s%run_times)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
开始主线程Thu Mar 14 13:35:29 2019
开始线程Thread-1 Thu Mar 14 13:35:29 2019
开始线程Thread-2 Thu Mar 14 13:35:29 2019
结束线程Thread-1 Thu Mar 14 13:35:32 2019
结束线程Thread-2 Thu Mar 14 13:35:32 2019
退出主线程Thu Mar 14 13:35:33 2019
运行时间4.004500389099121Process finished with exit code 0
#阻塞线程实例# codingutf-8
import threading
import timedef chiHuoGuo(people):print(%s 吃火锅的小伙伴-羊肉%s % (time.ctime(),people))time.sleep(1)print(%s 吃火锅的小伙伴-鱼丸%s % (time.ctime(),people))class myThread (threading.Thread): # 继承父类threading.Threaddef __init__(self, people, name):重写threading.Thread初始化内容threading.Thread.__init__(self)self.threadName nameself.people peopledef run(self): # 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数重写run方法print(开始线程: self.threadName)chiHuoGuo(self.people) # 执行任务print(qq交流群226296743)print(结束线程: self.name)print(yoyo请小伙伴开始吃火锅)# 创建新线程
thread1 myThread(xiaoming, Thread-1)
thread2 myThread(xiaowang, Thread-2)# 开启线程
thread1.start()
thread2.start()# 阻塞主线程等子线程结束
thread1.join()
thread2.join()time.sleep(0.1)
print(退出主线程吃火锅结束结账走人)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
yoyo请小伙伴开始吃火锅
开始线程: Thread-1
Thu Mar 14 13:41:10 2019 吃火锅的小伙伴-羊肉xiaoming
开始线程: Thread-2
Thu Mar 14 13:41:10 2019 吃火锅的小伙伴-羊肉xiaowang
Thu Mar 14 13:41:11 2019 吃火锅的小伙伴-鱼丸xiaowang
qq交流群226296743
结束线程: Thread-2
Thu Mar 14 13:41:11 2019 吃火锅的小伙伴-鱼丸xiaoming
qq交流群226296743
结束线程: Thread-1
退出主线程吃火锅结束结账走人Process finished with exit code 0
三、守护线程设置在start之前设置子线程A为守护线程主线程所在的进程内所有非守护线程统统运行完毕 无论子线程A有没有结束程序都结束
1、主线程退出时不等那些子线程完成那就设置子线程为守护线程thread1.setDaemon(True)
2、设置一个线程为守护线程就表示你在说这个线程不重要在进程退出时不用等待这个线程退出
3、程序在等待子线程结束才退出不需要设置线程守护或者显示调用thread1.setDaemon(False)
4、主线程是非守护线程只要还存在一个非守护线程程序就不会退出。
5、守护线程必须在start()方法调用之前设置如果不设置为守护线程程序会被无限挂起
6、当有多个子线程时守护线程就会等待所有的子线程运行完毕后守护线程才会挂掉(这一点和主线程是一样的,都是等待所有的子线程运行完毕后才会挂掉)。
7、调用线程对象的方法setDaemon(true)则可以将其设置为守护线程。在python中建议使用的是thread.demon true 使用这个方法可以检测数据合法性
8、setDaemon(True)此方法里面参数设置为True才会生效
9、对于主线程运行完毕指的是主线程所在的进程内所有非守护线程统统都运行完毕主线程才算运行完毕
10、守护线程实例
#设置线程1和线程2为守护线程
因为程序没有其他非守护线程所以当主线程运行完不等线程1和线程2就直接结束import threading,time
class MyThread(threading.Thread):#继承父类threading.Threaddef __init__(self,name,people):重写threading.Thread初始化内容super(MyThread,self).__init__()self.threadNamenameself.peoplepeopledef run(self):# 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数time.sleep(3)print(开始线程%s %s%(self.threadName,time.ctime()))print(结束线程%s %s%(self.threadName,time.ctime()))
start_timetime.time()
print(开始主线程%s%time.ctime())
thread1MyThread(Thread-1,王荔)
thread2MyThread(Thread-2,橙子)
thread1.setDaemon(True)#设置为守护线程
thread2.setDaemon(True)#设置为守护线程
thread1.start()
thread2.start()
print(退出主线程%s%time.ctime())
run_times(time.time()-start_time)
print(运行时间%s%run_times)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
开始主线程Thu Mar 14 13:59:09 2019
退出主线程Thu Mar 14 13:59:09 2019
运行时间0.0009975433349609375Process finished with exit code 0
#将线程2设置为守护线程
当线程1和主线程运行完程序立即结束故会存在2种结果
当线程1先结束就不会执行线程2结束
当线程2先结束就会出执行线程2结束import threading,time
class MyThread(threading.Thread):#继承父类threading.Threaddef __init__(self,name,people):重写threading.Thread初始化内容super(MyThread,self).__init__()self.threadNamenameself.peoplepeopledef run(self):# 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数print(开始线程%s %s%(self.threadName,time.ctime()))time.sleep(3)print(结束线程%s %s%(self.threadName,time.ctime()))
start_timetime.time()
print(开始主线程%s%time.ctime())
thread1MyThread(Thread-1,王荔)
thread2MyThread(Thread-2,橙子)
#thread1.setDaemon(True)#设置为守护线程
thread2.setDaemon(True)#设置为守护线程
thread2.start()
thread1.start()
print(退出主线程%s%time.ctime())
run_times(time.time()-start_time)
print(运行时间%s%run_times)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
开始主线程Thu Mar 14 14:11:07 2019
开始线程Thread-2 Thu Mar 14 14:11:07 2019
开始线程Thread-1 Thu Mar 14 14:11:07 2019
退出主线程Thu Mar 14 14:11:07 2019
运行时间0.0009958744049072266
结束线程Thread-2 Thu Mar 14 14:11:10 2019
结束线程Thread-1 Thu Mar 14 14:11:10 2019Process finished with exit code 0C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
开始主线程Thu Mar 14 14:13:03 2019
开始线程Thread-2 Thu Mar 14 14:13:03 2019
开始线程Thread-1 Thu Mar 14 14:13:03 2019
退出主线程Thu Mar 14 14:13:03 2019
运行时间0.0009908676147460938
结束线程Thread-1 Thu Mar 14 14:13:06 2019Process finished with exit code 0
#守护线程实例# codingutf-8
import threading
import timedef chiHuoGuo(people):print(%s 吃火锅的小伙伴-羊肉%s % (time.ctime(),people))time.sleep(1)print(%s 吃火锅的小伙伴-鱼丸%s % (time.ctime(),people))class myThread (threading.Thread): # 继承父类threading.Threaddef __init__(self, people, name):重写threading.Thread初始化内容threading.Thread.__init__(self)self.threadName nameself.people peopledef run(self): # 把要执行的代码写到run函数里面 线程在创建后会直接运行run函数重写run方法print(开始线程: self.threadName)chiHuoGuo(self.people) # 执行任务print(qq交流群226296743)print(结束线程: self.name)print(yoyo请小伙伴开始吃火锅)# 创建新线程
thread1 myThread(xiaoming, Thread-1)
thread2 myThread(xiaowang, Thread-2)# 守护线程setDaemon(True)
thread1.setDaemon(True) # 必须在start之前
thread2.setDaemon(True)# 开启线程
thread1.start()
thread2.start()time.sleep(0.1)
print(退出主线程吃火锅结束结账走人)C:\Users\wangli\PycharmProjects\AutoMation\venv\Scripts\python.exe C:/Users/wangli/PycharmProjects/AutoMation/case/test.py
yoyo请小伙伴开始吃火锅
开始线程: Thread-1
Thu Mar 14 14:22:20 2019 吃火锅的小伙伴-羊肉xiaoming
开始线程: Thread-2
Thu Mar 14 14:22:20 2019 吃火锅的小伙伴-羊肉xiaowang
退出主线程吃火锅结束结账走人Process finished with exit code 0
