Asynchronous function returning Task (Of String) or String?

Question

I am studying TAP , and I am wondering what feature of .NET allows you to use resultimplicitly in this method or interpret it as Task(Of String):

Public Async Function CheckHostInstructionAsync() As Task(Of String)
    Dim result As String
    result = Await pipeReader.ReadLineAsync() 'pipeReader is a System.IO.StreamReader
    If (result.Equals("exit", StringComparison.InvariantCultureIgnoreCase)) Then terminate = True
    Return result
End Function

First, if Await pipeReader.ReadLineAsync()"returns" a Task(Of String), why can I assign it resultwhich is declared as String?

Secondly, why can I say the Return resultreturn type though Task(Of String).

Answer 1

TAP ( ) async-await, . async await. Task ( , ), , .

pipeReader.ReadLineAsync() Task(Of String), String. await - , "" , .

result , , Task(Of String), String ( , )

Answer 2

Async/Await.

Async , , string, , , , .

Await Async, , Task, - , , , , (a string ).

Answer 3

Await pipeReader.ReadLineAsync() Task<string>, pipeReader.ReadLineAsync(). await ed, .

Secondly, returning a string from a method that should return Task<string>is done due to asyncdecoration, which tells the compiler to do this conversion for you.