RxPY – 可连接差操作符

publish

这个方法将把观测器转换成一个可连接的观测器。

语法

publish(mapper=None)

参数

mapper：可选。一个用于多次组播源值的函数，无需进行多次订阅。

例子

from rx import create, range, operators as op
import random
def test_observable(observer, scheduler):
   observer.on_next(random.random())
   observer.on_completed()
source = create(test_observable).pipe(op.publish())
test1 = source.subscribe(on_next = lambda i: print("From subscriber 1 - {0}".format(i)))
test2 = source.subscribe(on_next = lambda i: print("From subscriber 2 –
{0}".format(i)))
source.connect()

输出

E:\pyrx>python testrx.py
From subscriber 1 - 0.14751607273318490
From subscriber 2 - 0.1475160727331849

ref_count

这个操作符将使观测器成为一个正常的观测器。

语法

ref_count()

例子

from rx import create, operators as op
import random
def test_observable(observer, scheduler):
   observer.on_next(random.random())
source = create(test_observable).pipe(op.publish(),op.ref_count())
test1 = source.subscribe(on_next = lambda i: print("From subscriber 1 - {0}".format(i)))
test2 = source.subscribe(on_next = lambda i: print("From subscriber 2 - {0}".format(i)))

输出

E:\pyrx>python testrx.py
From subscriber 1 - 0.8230640432381131

replay

这个方法的工作原理与replaySubject类似。这个方法将返回相同的值，即使观察者已经发射了，并且一些订阅者迟迟没有订阅。

语法

replay()

例子

from rx import create, range, operators as op
import random
from threading import Timer
def test_observable(observer, scheduler):
   observer.on_next(random.random())
   observer.on_completed()
source = create(test_observable).pipe(op.replay())
test1 = source.subscribe(on_next = lambda i: print("From subscriber 1 - {0}".format(i)))
test2 = source.subscribe(on_next = lambda i: print("From subscriber 2 - {0}".format(i)))
source.connect()
print("subscriber called after delay ")
def last_subscriber():
   test3 = source.subscribe(on_next = lambda i: print("From subscriber 3 - {0}".format(i)))
t = Timer(5.0, last_subscriber)
t.start()

输出

E:\pyrx>python testrx.py
From subscriber 1 - 0.8340998157725388
From subscriber 2 - 0.8340998157725388
subscriber called after delay
From subscriber 3 - 0.8340998157725388