' Three things to note about writing an Async Function:

'  - The function has an Async modifier.

'  - Its return type is Task or Task(Of T). (See "Return Types" section.)

'  - As a matter of convention, its name ends in "Async".

Async Function AccessTheWebAsync() As Task(Of Integer)

    Using client As New HttpClient()

        ' Call and await separately.

        '  - AccessTheWebAsync can do other things while GetStringAsync is also running.

        '  - getStringTask stores the task we get from the call to GetStringAsync.

        '  - Task(Of String) means it is a task which returns a String when it is done.

        Dim getStringTask As Task(Of String) =

            client.GetStringAsync("https://docs.microsoft.com/dotnet")

        ' You can do other work here that doesn't rely on the string from GetStringAsync.

        DoIndependentWork()

        ' The Await operator suspends AccessTheWebAsync.

        '  - AccessTheWebAsync does not continue until getStringTask is complete.

        '  - Meanwhile, control returns to the caller of AccessTheWebAsync.

        '  - Control resumes here when getStringTask is complete.

        '  - The Await operator then retrieves the String result from getStringTask.

        Dim urlContents As String = Await getStringTask

        ' The Return statement specifies an Integer result.

        ' A method which awaits AccessTheWebAsync receives the Length value.

        Return urlContents.Length



    End Using



End Function