RxPY - 连接操作符

publish

此方法会将可观察对象转换为可连接可观察对象。

语法

publish(mapper=None)

参数

mapper：可选。用于多次多播源值但在不需要多次订阅时的函数。

示例

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

此操作符会使可观察对象变成一个常规可观察对象。

语法

ref_count()

示例

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

此方法的工作方式类似于 replaySubject。该方法会返回相同的值，即使可观察对象已经发出，且某些订阅者延迟订阅。

语法

replay()

示例

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