Reactive extensions for dot net - departmental presentation

1. Reactive
Extensions for
.NET
Previously Linq to Events
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2. IObserver - Observable
• Comparable to IEnumerable and IEnumerator
• Built into .Net 4.0, In the System namespace
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3. Push vs. Pull
• Pull – IEnumerable
o Gather a set of data
o Do something for each item in the set
• Push – IObservable
o Decide what you want to do for each item
o React to each item as it is introduced
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4. Linq Extensions
• Extension methods based on IEnumerable<T>
• Chainable
• Filtering – Where
• Projection – Select
• Paging – Take, Skip
• Composition – Join
• Rearrange – OrderBy
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5. Reactive Extensions
• Extension methods based on IObservable<T>
• Chainable
• Filtering – Where
• Projection – Select
• Paging – TakeUntil, SkipUntil
• Composition – Merge, Zip, CombineLatest
• Time based – Interval, Delay, Throttle, Sample
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6. Merge
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7. SkipUntil - TakeUntil
green.SkipUntil(blue).TakeUntil(red)
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8. Buffer
1 2 3 4 5 6 7
1 2 3 4 5 6
2 3 4 5 6 7
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9. Subscriptions
• Joining an IObserver to an IObservable
• Returns an IDisposable, Dispose to unsubscribe
• Extension methods for Subscribe overrides
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10. Scheduler
• Most extensions that are time based have overrides
that accept a scheduler.
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11. Standard Event
Composition
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12. Converting Standard
Events into Observables
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13. Rx Event Composition
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14. Rx Event Projection
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15. Rx IObservable Chaining
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16. Rx Multiple Subscribers
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17. Rx Multiple Subscribers
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