Asinxron dasturlash

Module Dastur
    Async Function Tayyorlash(nom As String,
                              vaqt As Integer) As Task(Of String)
        Await Task.Delay(vaqt)
        Return $"{nom} tayyor"
    End Function

    Sub Main()
        MainAsync().GetAwaiter().GetResult()
    End Sub

    Async Function MainAsync() As Task
        Console.WriteLine("Boshlandi")

        Dim natija As String = Await Tayyorlash("Choy", 50)
        Console.WriteLine(natija)

        Console.WriteLine("Tugadi")
    End Function
End Module

Module Dastur
    Async Function Hisobla(a As Integer, b As Integer) As Task(Of Integer)
        Await Task.Delay(30)
        Return a + b
    End Function

    Async Function Xabar(matn As String) As Task
        Await Task.Delay(30)
        Console.WriteLine($"Xabar: {matn}")
    End Function

    Sub Main()
        MainAsync().GetAwaiter().GetResult()
    End Sub

    Async Function MainAsync() As Task
        Dim yigindi As Integer = Await Hisobla(15, 27)
        Console.WriteLine(yigindi)

        Await Xabar("yuborildi")
    End Function
End Module

Imports System.Diagnostics

Module Dastur
    Async Function Ish(nom As String) As Task(Of String)
        Await Task.Delay(200)
        Return nom
    End Function

    Sub Main()
        MainAsync().GetAwaiter().GetResult()
    End Sub

    Async Function MainAsync() As Task
        Dim soat As Stopwatch = Stopwatch.StartNew()
        Dim a As String = Await Ish("A")
        Dim b As String = Await Ish("B")
        Dim c As String = Await Ish("C")
        soat.Stop()
        Dim ketmaKet As Long = soat.ElapsedMilliseconds

        soat.Restart()
        Dim vazifalar() As Task(Of String) = {Ish("A"), Ish("B"), Ish("C")}
        Dim natijalar() As String = Await Task.WhenAll(vazifalar)
        soat.Stop()
        Dim parallel As Long = soat.ElapsedMilliseconds

        Console.WriteLine($"Natijalar: {String.Join(", ", natijalar)}")
        Console.WriteLine($"Ketma-ket 500 ms dan ko'pmi: {ketmaKet > 500}")
        Console.WriteLine($"Parallel 400 ms dan kammi: {parallel < 400}")
        Console.WriteLine($"Parallel tezroqmi: {parallel < ketmaKet}")
    End Function
End Module

Module Dastur
    Async Function Ish(nom As String, vaqt As Integer) As Task(Of String)
        Await Task.Delay(vaqt)
        Return nom
    End Function

    Sub Main()
        MainAsync().GetAwaiter().GetResult()
    End Sub

    Async Function MainAsync() As Task
        Dim vazifalar() As Task(Of String) = {
            Ish("birinchi", 150),
            Ish("ikkinchi", 50),
            Ish("uchinchi", 100)
        }

        Dim natijalar() As String = Await Task.WhenAll(vazifalar)
        Console.WriteLine(String.Join(", ", natijalar))
    End Function
End Module

Module Dastur
    Async Function Xavfli(muvaffaqiyat As Boolean) As Task(Of Integer)
        Await Task.Delay(20)
        If Not muvaffaqiyat Then
            Throw New InvalidOperationException("ish bajarilmadi")
        End If
        Return 42
    End Function

    Sub Main()
        MainAsync().GetAwaiter().GetResult()
    End Sub

    Async Function MainAsync() As Task
        Try
            Console.WriteLine(Await Xavfli(True))
            Console.WriteLine(Await Xavfli(False))
        Catch ex As InvalidOperationException
            Console.WriteLine($"Ushlandi: {ex.Message}")
        End Try
    End Function
End Module

' Yomon - dasturni qotirib qo'yishi mumkin
Dim natija As String = Tayyorlash("Choy", 100).Result

' To'g'ri
Dim natija As String = Await Tayyorlash("Choy", 100)

' Yomon - xatoni ushlab bo'lmaydi
Async Sub Yuborish()
    Await Task.Delay(100)
    Throw New Exception("yo'qoladi")
End Sub

' To'g'ri
Async Function Yuborish() As Task
    Await Task.Delay(100)
    Throw New Exception("ushlash mumkin")
End Function

Imports System.IO

Module Dastur
    Async Function FaylYoz(nom As String, matn As String) As Task
        Await File.WriteAllTextAsync(nom, matn)
    End Function

    Sub Main()
        MainAsync().GetAwaiter().GetResult()
    End Sub

    Async Function MainAsync() As Task
        Dim fayllar() As String = {"a.txt", "b.txt", "c.txt"}

        Dim vazifalar As New List(Of Task)
        For i As Integer = 0 To fayllar.Length - 1
            vazifalar.Add(FaylYoz(fayllar(i), $"Fayl raqami {i + 1}"))
        Next

        Await Task.WhenAll(vazifalar)
        Console.WriteLine("Hamma fayl yozildi")

        For Each f As String In fayllar
            Console.WriteLine(Await File.ReadAllTextAsync(f))
            File.Delete(f)
        Next
    End Function
End Module