RxPY - 連線運算子

publish

此方法會將可觀察物件轉換為可連線可觀察物件。

語法

publish(mapper=None)

引數

mapper：可選。用於多次多播源值但在不需要多次訂閱時的函式。

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()

輸出

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

ref_count

此運算子會使可觀察物件變成一個常規可觀察物件。

語法

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)))

輸出

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

replay

此方法的工作方式類似於 replaySubject。該方法會返回相同的值，即使可觀察物件已經發出，且某些訂閱者延遲訂閱。

語法

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()

輸出

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