PowerBuilder

Async Methods Returning an String

See more Async Examples

Demonstrates how to call an asynchronous method that returns a string. This example sends an HTTPS GET request to a URL and gets the HTML response. PowerBuilder

integer li_rc
integer li_Success
oleobject loo_Http
oleobject loo_Task
string ls_Html

li_Success = 0

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

loo_Http = create oleobject
li_rc = loo_Http.ConnectToNewObject("Chilkat.Http")
if li_rc < 0 then
    destroy loo_Http
    MessageBox("Error","Connecting to COM object failed")
    return
end if

loo_Task = loo_Http.QuickGetStrAsync("https://www.chilkatsoft.com/helloWorld.html")
if loo_Http.LastMethodSuccess = 0 then
    Write-Debug loo_Http.LastErrorText
    destroy loo_Http
    return
end if

// Start the background task.
li_Success = loo_Task.Run()
if not li_Success then
    Write-Debug loo_Task.LastErrorText
    destroy loo_Task
    destroy loo_Http
    return
end if

// The application is now free to do anything else

// For this example, we'll simply sleep and periodically
// check to see if the HTTPS GET if finished.
do while loo_Task.Finished <> 1
    // Sleep 100 ms.
    loo_Task.SleepMs(100)
loop

// A finished task could be one that was canceled, aborted, or truly finished.  

// If the task was "canceled", it was canceled prior to actually starting.  This could
// happen if the task was canceled while waiting in a thread pool queue to be scheduled by Chilkat's
// background thread pool scheduler.  

// If the task was "aborted", it indicates that it was canceled while running in a background thread.  
// The ResultErrorText will likely indicate that the task was aborted.

// If the task "completed", then it ran to completion, but the actual success/failure of the method
// is determined by the result obtained via a GetResult* method.  (A "completed" task will
// have a StatusInt equal to 7.   If the task finished, but was not completed, then it must've
// been aborted or canceled:
if loo_Task.StatusInt <> 7 then
    Write-Debug "Task did not complete."
    Write-Debug "task status: " + loo_Task.Status
    destroy loo_Task
    destroy loo_Http
    return
end if

// The QuickGetStr method returns a string.  Therefore, after the task is finished,
// we can get the string result by calling GetResultString.  This is the return value had
// we called QuickGetStr synchronously.
ls_Html = loo_Task.GetResultString()

Write-Debug ls_Html

destroy loo_Task


destroy loo_Http