等待的同时F＃多个事​​件的任何情况 [英] Wait for any event of multiple events simultaneously in F#

问题描述

在F＃我知道如何以异步方式等待使用一个事件 Async.AwaitEvent ：

 让测试= {异步
  让！此举= Async.AwaitEvent（form.MouseMove）
  ......把手举...}
 

假设我想等到了<$c$c>MouseMove或<一个href=\"http://msdn.microsoft.com/en-us/library/system.windows.forms.control.keydown.aspx\"><$c$c>KeyDown事件。我想有这样的事情：

 让！ moveOrKeyDown = Async.AwaitEvent（form.MouseMove，form.KeyDown）
 

此功能不存在，但有另一种方式来做到这一点？

解决方案

 让ignoreEvent E = Event.map忽略Ë让合并= Event.merge（ignoreEvent f.KeyDown）（ignoreEvent f.MouseMove）
Async.AwaitEvent合并
 

编辑：另一个preserves版本原稿类型

 让合并= Event.merge（f.KeyDown |＆GT; Event.map Choice1Of2）（f.MouseMove |＆GT; Event.map Choice2Of2）
Async.AwaitEvent合并
 

编辑2 ：根据意见的托马斯Petricek 的

 让E1 = f.KeyDown |＆GT; Observable.map Choice1Of2
让E2 = f.MouseMove |＆GT; Observable.map Choice2Of2
让！ EVT = Observable.merge E1 E2 |＆GT; Async.AwaitObservable
 

的 AwaitObservable 的原始可以从这里采取A>（'无演示在Silverlight'由Tomas Petricek）。

In F# I know how to wait asynchronously for one event using Async.AwaitEvent:

let test = async {
  let! move = Async.AwaitEvent(form.MouseMove)
  ...handle move... }

Suppose I want to wait for either the MouseMove or the KeyDown event. I'd like to have something like this:

let! moveOrKeyDown = Async.AwaitEvent(form.MouseMove, form.KeyDown)

This function doesn't exist but is there another way to do this?

解决方案

let ignoreEvent e = Event.map ignore e

let merged = Event.merge (ignoreEvent f.KeyDown) (ignoreEvent f.MouseMove)
Async.AwaitEvent merged

EDIT: another version that preserves original types

let merged = Event.merge (f.KeyDown |> Event.map Choice1Of2) (f.MouseMove |> Event.map Choice2Of2)
Async.AwaitEvent merged

EDIT 2: according to comments of Tomas Petricek

let e1 = f.KeyDown |> Observable.map Choice1Of2
let e2 = f.MouseMove |> Observable.map Choice2Of2
let! evt = Observable.merge e1 e2 |> Async.AwaitObservable

AwaitObservable primitive can be taken from here ('Reactive demos in Silverlight' by Tomas Petricek).

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