Visual FoxPro

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. Visual FoxPro

LOCAL lnSuccess
LOCAL loSock
LOCAL loTask
LOCAL lnCount
LOCAL s
LOCAL loConnection
LOCAL loAcceptedConnection

lnSuccess = 0

* 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 (1/0), get returned value by calling GetResultBool.
* For example..

loSock = CreateObject('Chilkat.Socket')

* --------------------------------------------------------------
* Synchronous call returning 1/0
lnSuccess = loSock.Connect("example.com",443,1,5000)

* --------------------------------------------------------------
* Asynchronous call
loTask = loSock.ConnectAsync("example.com",443,1,5000)
* ...
loTask.Run()
* ...
* ...
* Get the status (1/0) value returned by the synchronous method called in the background thread.
lnSuccess = loTask.GetResultBool()

* --------------------------------------------------------------
* Synchronous call returning an integer
lnCount = loSock.ReceiveCount()

* --------------------------------------------------------------
* Asynchronous call
loTask = loSock.ReceiveCountAsync()
* ...
loTask.Run()
* ...
* ...
* Get the integer value returned by the synchronous method called in the background thread.
lnCount = loTask.GetResultInt()

* --------------------------------------------------------------
* Synchronous call returning an string
s = loSock.ReceiveString()

* --------------------------------------------------------------
* Asynchronous call
loTask = loSock.ReceiveStringAsync()
* ...
loTask.Run()
* ...
* ...
* Get the string value returned by the synchronous method called in the background thread.
s = loTask.GetResultString()

* --------------------------------------------------------------
* Synchronous call returning an object
loConnection = loSock.AcceptNextConnection(5000)

* --------------------------------------------------------------
* Asynchronous call
loTask = loSock.AcceptNextConnectionAsync()
* ...
loTask.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).
loAcceptedConnection = CreateObject('Chilkat.Socket')
IF (loTask.TaskSuccess = 1) THEN
    lnSuccess = loAcceptedConnection.LoadTaskResult(loTask)
ENDIF

RELEASE loSock
RELEASE loAcceptedConnection