private static void MergingObservableOfObservables()
{
Demo.DisplayHeader("The Merge operator - allows also to merge observables emitted from another observable");
IObservable <string> texts = ObservableEx.FromValues("Hello", "World");
texts
.Select(txt => Observable.Return(txt + "-Result"))
.Merge()
.SubscribeConsole("Merging from observable");
}
private static void ZippingTwoObservables()
{
Demo.DisplayHeader("The Zip operator - combines values with the same index from two observables");
//temperatures from two sensors (in celsius)
IObservable <double> temp1 = ObservableEx.FromValues(20.0, 21, 22);
IObservable <double> temp2 = ObservableEx.FromValues(22.0, 21, 24);
temp1
.Zip(temp2, (t1, t2) => (t1 + t2) / 2)
.SubscribeConsole("Avg Temp.");
}
private static void DelayingEachNotificationIndependently()
{
Demo.DisplayHeader("Throttle operator - each notification can be shifted independently by providing observable that signals the delay is over");
var observable = ObservableEx.FromValues(4, 1, 2, 3);
observable
.Timestamp()
.Delay(x => Observable.Timer(TimeSpan.FromSeconds(x.Value)))
.Timestamp()
.RunExample("Independent Delay");
}
private static void AddToCompositeDisposable()
{
Demo.DisplayHeader("AddToCompositeDisposable extensions method - useful for keeping your observable pipeline fluent");
var compositeDisposable = new CompositeDisposable();
IObservable <string> observable = ObservableEx.FromValues("Rx", "For", "The", "Win");
observable.Where(x => x.Length % 2 == 0)
.Select(x => x.ToUpper())
.Subscribe(x => Console.WriteLine(x))
.AddToCompositeDisposable(compositeDisposable);
observable.Where(x => x.Length % 2 == 1)
.Select(x => x.ToLower())
.Subscribe(x => Console.WriteLine(x))
.AddToCompositeDisposable(compositeDisposable);
}
public static void SubscribeOnAndObserveOn()
{
Demo.DisplayHeader("using SubscribeOn and ObserveOn together and their effect");
ObservableEx.FromValues(0, 1, 2, 3, 4, 5)
.Take(3)
.LogWithThread("A")
.Where(x => x % 2 == 0)
.LogWithThread("B")
.SubscribeOn(NewThreadScheduler.Default)
.LogWithThread("C")
.Select(x => x * x)
.LogWithThread("D")
.ObserveOn(TaskPoolScheduler.Default)
.LogWithThread("E")
.RunExample("squares by time");
}
private static void AggreagateResultInAWindow()
{
Demo.DisplayHeader("The Window operator - each window is an observable that can be used with an aggregation function");
var donationsWindow1 = ObservableEx.FromValues(50M, 55, 60);
var donationsWindow2 = ObservableEx.FromValues(49M, 48, 45);
IObservable <decimal> donations =
donationsWindow1.Concat(donationsWindow2.DelaySubscription(TimeSpan.FromSeconds(1.5)));
var windows = donations.Window(TimeSpan.FromSeconds(1));
var donationsSums =
from window in windows.Do(_ => Console.WriteLine("New Window"))
from sum in window.Scan((prevSum, donation) => prevSum + donation)
select sum;
donationsSums.RunExample("donations in shift");
}
private static void GroupBy()
{
var people = ObservableEx.FromValues(
new Person()
{
Gender = Gender.Male, Age = 21
},
new Person()
{
Gender = Gender.Female, Age = 31
},
new Person()
{
Gender = Gender.Male, Age = 23
},
new Person()
{
Gender = Gender.Female, Age = 33
});
var genderAge =
from gender in people.GroupBy(p => p.Gender)
from avg in gender.Average(p => p.Age)
select new { Gender = gender.Key, AvgAge = avg };
genderAge.SubscribeConsole("Gender Age");
//
// Grouping with Query Syntax GroupBy clause
//
//var genderAge2 =
// from p in people
// group p by p.Gender
// into gender
// from avg in gender.Average(p => p.Age)
// select new { Gender = gender.Key, AvgAge = avg };
}