VB.NET

Understanding Async Function Return Values

See more Async Examples

Explains how to get the return value of the function called synchonously in the background thread. VB.NET

Dim success As Boolean = False

' Some Chilkat functions can be called asynchronously.
' If a function "Func" can be called asynchronously, there will be a corresponding "FuncAsync" function that returns a Task object.
' 
' When Task.Run is called, the synchronous "Func" runs in a background thread.
' 

' For Chilkat methods that return a status (True/False), get returned value by calling GetResultBool.
' For example..

Dim sock As New Chilkat.Socket

' --------------------------------------------------------------
' Synchronous call returning True/False
success = sock.Connect("example.com",443,True,5000)

' --------------------------------------------------------------
' Asynchronous call
Dim task As Chilkat.Task = sock.ConnectAsync("example.com",443,True,5000)
' ...
task.Run()
' ...
' ...
' Get the status (True/False) value returned by the synchronous method called in the background thread.
success = task.GetResultBool()

' --------------------------------------------------------------
' Synchronous call returning an integer
Dim count As Integer = sock.ReceiveCount()

' --------------------------------------------------------------
' Asynchronous call
task = sock.ReceiveCountAsync()
' ...
task.Run()
' ...
' ...
' Get the integer value returned by the synchronous method called in the background thread.
count = task.GetResultInt()

' --------------------------------------------------------------
' Synchronous call returning an string
Dim s As String = sock.ReceiveString()

' --------------------------------------------------------------
' Asynchronous call
task = sock.ReceiveStringAsync()
' ...
task.Run()
' ...
' ...
' Get the string value returned by the synchronous method called in the background thread.
s = task.GetResultString()

' --------------------------------------------------------------
' Synchronous call returning an object
Dim connection As Chilkat.Socket = sock.AcceptNextConnection(5000)

' --------------------------------------------------------------
' Asynchronous call
task = sock.AcceptNextConnectionAsync()
' ...
task.Run()
' ...
' ...
' Get the object returned by the synchronous method called in the background thread.
' We do this a little differently.  We create an new object of the same type,
' and then load it with the returned object (assuming it was not null).
Dim acceptedConnection As New Chilkat.Socket
If (task.TaskSuccess = True) Then
    success = acceptedConnection.LoadTaskResult(task)
End If