为什么Async.RunSynchronously挂起? [英] Why is Async.RunSynchronously hanging?

问题描述

在我的f#项目中，我正在调用一个c#库，该库向我返回了一个Task.当我尝试在f#项目中执行此操作时，什么也没发生.

In my f# project, I'm calling a c# library that returns me a Task. When I try to do this in my f# project, nothing happens.

let str = getName() |> Async.AwaitTask |> Async.RunSynchronously

但是，如果我更新代码以使用异步工作流，它将不再挂起.调用Async.RunSynchronously时我在做什么错了?

However, if I update my code to use an async workfolow, it doesn't hang anymore. What am I doing wrong when calling Async.RunSynchronously?

async {
     let! str = getName() |> Async.AwaitTask
     //Do something with str
}

推荐答案

在第二个示例中，您只是构建 异步工作流程，但不要实际上运行.

In your second example you just build async workflow, but don't actually run it.

以这种方式进行设计，因此您可以定义复杂的工作流而不必立即运行它的每个异步部分，而可以在一切就绪并准备就绪时运行整个事情.

It is designed that way so you could define a complex workflow without running every async part of it immediately, but instead run the whole thing when it's good and ready.

要运行它，您需要调用 Async.RunSynchronously 或 Async.StartAsTask :

In order to run it you need to call Async.RunSynchronously or Async.StartAsTask:

async {
 let! str = getName() |> Async.AwaitTask
 //Do something with str
} |> Async.RunSynchronously

此外，如果要做需要使用 Task ，则最好使用

Also, if you do need to work with Tasks, it's probably better to use TaskBuilder.fs instead of Async.

这篇关于为什么Async.RunSynchronously挂起?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！