rxjs

Let's explore a different use of the multicast () operator in RxJS, where can provide a selector function as a sandbox The where the shared Observable is available.When we have the code like below: var result = Rx.Observable.interval (1000 ). Take (6 ). do (x = Console.log ( ' source + X"). Map (x => Math.random ()); var Delayedresult = result.delay (500 Span style= "color: #000000;" >); var merged = Result.merge (Delayedresult); Merged.su

(function (x) {Console.log ('Next'+x);}, function (err) {Console.log ('Error'+err);}, function () {Console.log (' Done');});/*"Next 1" "Next 2" "Next 3" "Done"*/=frompromiosevar foo = rx.observable. from (Prom); Foo.subscribe (function (x) { console.log (' + x.status);}, function (err) { console.log (' + err);}, function () { Console.log ('done');});From iterator:function*Generator () {yield Ten; yield -; yield -;}variterator =generator ();varFoo = rx.observable. from(iterator); Foo.subsc

The Observer object has the functions next () and error (). In this lesson we'll see the other (and last) function available on observers, complete (), and its purpose.Completion is an important concept, as we'll see later on. Imagine If you want to concatenate and observables. You can have only does that if the first one ends. Then you know this second observable takes over.Completion is also important in other ways. For instance, let's say that observer are only interested in the last value th

= Rx.Observable.interval ($). Take (5). zip (Rx.Observable.of (' A ', ' B ', ' A ', ' a ', ' B '), (x, y) =y);varCOMPARFN = (x, y) = = { returnX.tolowercase () = = =y.tolowercase ();}/*--a--b--a--a--b| Distinct--a--b---------|*/varresult =foo.distinct (COMPARFN); Result.subscribe (function(x) {Console.log (' next ' +x); }, function(ERR) {console.log (' error ' +err); }, function() {console.log (' done ')); },); /*"Next A" "Next B" "Done"*/With FLUSHERFN:varFoo = Rx.Observable.interval ($)

Buffertoggle (open:observable, () = close:observalbe:observalbeBuffertoggle take both args, first is opening observable, and Seconde is a function which return an observable for closing.The closeing Observalbe only execute after opening emit value.Const source$ = Rx.Observable.interval (500); Const open$= Rx.Observable.interval (1500); Const close$= Rx.Observable.interval (1000);/**---0---1---2---3---4---5---6---7---8---9----.... (source)-----------1-----------2-----------3--------...

We just saw map which is a transformation operator. There is a couple of categories of operators, such as filtering, combination, flattening, etc. One of these categories is the utility operators. The most important utility operator do are, useful for debugging.varFoo = Rx.Observable.interval ($). Take (4);/*foo:---0---1---2---3--... do (x = Console.log (' before ' + x))---0---1---2---3--... map (x = x * 2)---0---2---4---6--... do (x = Console.log (' after ' + x))---0---2---4---6--...*/varBar =f

$. Filter (data)= = Data.count = = =parseint (Data.text)). Reduce ((ACC, Curr)= + ACC + 1, 0). Repeat (). Subscribe ((x)= = Document.queryselector (' #score '). InnerHTML =' ${x} ', Err=Console.log (Err), ()= = Console.log (' Complete ') );DOCTYPE HTML>HTML>Head> MetaCharSet= "Utf-8"> Metaname= "Viewport"content= "Width=device-width"> Scriptsrc= "https://npmcdn.com/@reactivex/[email protected]/dist/global/rx.umd.js">Script> title>JS Bintitle>Head>Body>ButtonID= "Start">StartButton>ButtonI

You often need-to-render out data before your stream begins from a click or another user interaction. This lessons shows how to use to startWith set the initial output before you trigger your stream.Const OBSERVABLE =Rx.observable;const Startbutton= Document.queryselector (' #start '); Const Stopbutton= Document.queryselector (' #stop '); Const start$= Observable.fromevent (Startbutton, ' click ')); Const interval$= Observable.interval (1000); Const stop$= Observable.fromevent (Stopbutton, ' cli

, Spritecontainer) {//All of the mouse event sequences look like this: //seq ([{pagex:22, pagey:3423, offsetx:14, offsety:22},,,]) varspritemousedowns = Observable.fromevent (Sprite, "MouseDown"), Spritecontainermousemoves= Observable.fromevent (Spritecontainer, "MouseMove"), Spritecontainermouseups= Observable.fromevent (Spritecontainer, "MouseUp"), //Create a sequence that looks like this: //seq ([{pagex:22, pagey:4080},,, {pagex:24, pagey:4082},,,])Spritemousedrags =//For

By default, Inputs would push input events into the stream. This lesson shows the map input event into the text you actually want.DOCTYPE HTML>HTML>Head> MetaCharSet= "Utf-8"> Metaname= "Viewport"content= "Width=device-width"> Scriptsrc= "https://npmcdn.com/@reactivex/[email protected]/dist/global/rx.umd.js">Script> title>JS Bintitle>Head>Body>inputtype= "text"ID= "Input">Body>HTML>const input = Document.queryselector (' #input '); const input$ = observable.fromevent (input, ' input ') = ev

Observable.prototype.debug =function (message:any) {return This. Do(Next)= { if(!environment.production) {console.log (message, next); }}, (Err)= { if(!environment.production) {console.error (message, Err)}}, ()= { if(!environment.production) {console.info ("Observable completed", Message)} } );}; DECLARE module'rxjs/observable' { InterfaceObservable{debug: (... any)= observable }}[RxJS] Add Debug method to Observable in TypeScr

A Subject is a type that implements both Observer and Observable types. As an Observer, it can subscribe to observables, and as an Observable it can produce values and has OBSERVERSW subscribe It.First time I Read Implements both Observer and Observable types I was quite confused.As a Observable:varSubject =NewRx.subject ();varSubscription =Subject.subscribe (function OnNext (x) {Console.log ('OnNext:'+x); }, function OnError (e) {Console.log ('OnError:'+e.message); }, Function onc

Combining input streams then using scan -to-track the results are a common scenario when coding with streams. This lesson walks you through setting up the buttons and merging their input events together to build a streaming Counter Component.Const Counterstream = Componentfromstream ( = = = Createeventhandler (); = Createeventhandler (); return props$ switchmap ( = observable.merge ( oninc$.mapto (1), ondec$ . Mapto (-1) ) . Startwith (propos.valu

(y =Math.ceil ((y +Window.innerheight)/(This.itemheight *(This.numberofitems)));Private pagebyresize$ = Observable.fromevent (Window"Resize"). Debouncetime (). Map (_ =Math.ceil ((Window.innerheight +DOCUMENT.BODY.SCROLLTOP)/(This.itemheight *(This.numberofitems)));Private pagetoload$ = Observable. Merge (this.pagebymanual$,this.pagebyscroll$,this.pagebyresize$). Distinct (). Filter (page =This.cache[page-1] = = =undefined); itemresults$ =this.pagetoload$. Do (_ =This.loading =true). FlatMap ((

actually ' subject ' partten, works both as Observer and Observable.Subject:ConstObservable = Rx.Observable.interval ( +). Take (5);ConstObservera ={next:function (x) {Console.log ("A Next"+x)}, Error:function (x) {Console.error ("A Error"+x)}, Complete:function () {Console.log ("A Done") },};ConstObserverb ={next:function (x) {Console.log ("B Next"+x)}, Error:function (x) {Console.error ("B Error"+x)}, Complete:function () {Console.log ("B Done") },}; const subject = new rx.subject (); /*Co

Observer subscribe to a behaviorsubject. It receivces the last emitted value and then all the subsequent values. Behaviorsubject requires that we provide a starting value, so taht all observers would always receive a value when they sub scribe to a behaviorsubject.Imagine we want to retreve a remote file and print it contents on an HTML page, but we wnat placeholder text while we Wai T for the contents. We can use a behaviorsubject for this.var New Rx.behaviorsubject ('waiting for content'); Sub

just subscribe observer returnSUBJECT.SUBSCRIBE (Observer); })}varProducts = getproducts ('/products ');//Would trigger request and receive the response when readProducts.subscribe (functionOnNext (Result) {Console.log (' result 1: '), Result.response)},functionOnError (Error) {Console.log (' error '), error)});//Would receive the result immediately because it is cachedSetTimeout (function() {Products.subscribe (functionOnNext (Result) {Console.log (' Result 2: '), Result.response)},function

All of the combination operators take, or more observables as input. These operators may also is alternatively called "vertical combination operators", because of how they work in a marble di Agram. Next, we'll learn about scan (), which are an important "horizontal combination operator".varclick$ = Rx.Observable.fromEvent (Document.queryselector ("#btn"), ' click ');/*----EV-----EV---EV----EV----EV----.. Mapto (1)----1-----1---1----1----1-----.. Scan (ACC, Curr) = acc + curr, 0)----1------2-

Debounce is known-a rate-limiting operator, but it's not the only one. This lessons introduces-throttletime and throttle, which only drop events (without delaying them) to accomplish rat E limiting.Throttletime (number): first emits, then cause silencevar foo = Rx.Observable.interval ($). Take (5); /* --0--1--2--3--4| Debouncetime (+)//waits for silence, then emits throttletime (+)//first emits, then causes silence--0-----2--- --4| */ var result = Foo.throttletime (+); Result.subscribe ( func

Operator Combinelatest is isn't the only And-style combinator. In this lesson we'll explore Withlatestfrom, another and-style combination operator, and how it works essentially as map () operator, with some combination properties.varFoo = Rx.Observable.interval (400). zip (Rx.Observable.of (' h ', ' e ', ' l ', ' l ', ' O '), (__, x) = =x);varBar = Rx.Observable.interval (300). zip (Rx.Observable.of (0,1,1,0,0,1,0,0,1), (__, x) = =x);/*----h----e----l----l----o| (foo)--0--1--1--0--0--1--0--0--