这篇文章主要介绍“python多线程中获取函数返回值的方法有哪些”,在日常操作中,相信很多人在python多线程中获取函数返回值的方法有哪些问题上存在疑惑,小编查阅了各式资料,整理出简单好用的操作方法,希望对大家解答”python多线程中获取函数返回值的方法有哪些”的疑惑有所帮助!接下来,请跟着小编一起来学习吧!
方法一:使用队列
import queue
import threading
import sys
import time
q=queue.Queue()
def func1(x,y):
func_name = sys._getframe().f_code.co_name # 获取函数名
print("%s run ....." % func_name)
q.put((x+y,func_name))
def func2(x,y):
func_name = sys._getframe().f_code.co_name
print("%s run ...." %func_name)
q.put((x-y,func_name))
if __name__ == "__main__":
result=[]
t1=threading.Thread(target=func1,name="thread1",args=(10,5))
t2=threading.Thread(target=func2,name="thread2",args=(20,1))
print('*'*20)
t1.start()
t2.start()
t1.join()
t2.join()
while not q.empty():# 队列为空返回True,反之False
result.append(q.get())
for item in result:
if item[1] == func1.__name__:
print("%s return value is: %s" %(item[1],item[0]))
elif item[1] == func2.__name__:
print("%s return value is: %s" %(item[1],item[0]))
运行结果:
********************
func1 run .....
func2 run ....
func1 return value is: 15
func2 return value is: 19
方法二: 封装 threading.Thread,重写 run 方法
class mythread(threading.Thread):
def __init__(self,func,args=()):
super(mythread, self).__init__()
self.func=func
self.args=args
def run(self):
self.result=self.func(*self.args)
def get_result(self):
try:
return self.result
except Exception:
return None
def foo(a,b,c):
time.sleep(1)
return a*2,b*2,c*2
li = []
for i in range(4):
t=mythread(foo,args=(i,i+1,i+2))
li.append(t)
t.start()
for t in li:
t.join()
print(t.get_result())
# 运行结果
(0, 2, 4)
(2, 4, 6)
(4, 6, 8)
(6, 8, 10)
方法三:使用进程池
def func(msg):
print("msg:",msg)
time.sleep(3)
print("end")
return "done" + msg
if __name__ == "__main__":
pool = multiprocessing.Pool(processes=4)
result = []
for i in range(3):
msg = "hello %d" %i
result.append(pool.apply_async(func,(msg,)))
pool.close()
pool.join()
for res in result:
print(res)
print(":::",res.get())
# 运行结果
msg: hello 0
msg: hello 1
msg: hello 2
end
end
end
<multiprocessing.pool.ApplyResult object at 0x0000027BF6B3F0D0>
::: donehello 0
<multiprocessing.pool.ApplyResult object at 0x0000027BF6F4FDF0>
::: donehello 1
<multiprocessing.pool.ApplyResult object at 0x0000027BF6F4FDC0>
::: donehello 2