(DataFlex) Getting the HTTP Response after an Asynchronous HTTP Request Completes

Some HTTP methods return an HTTP response object. This example demonstrates how to obtain the HTTP response object for such a method when calling asynchronously.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoChilkatGlob
    Boolean iSuccess
    Handle hoHttp
    Variant vTask
    Handle hoTask
    Handle hoResp
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    // All Chilkat classes can be unlocked at once at the beginning of a program
    // by calling UnlockBundle.  It requires a Bundle unlock code.
    Get Create (RefClass(cComChilkatGlobal)) To hoChilkatGlob
    If (Not(IsComObjectCreated(hoChilkatGlob))) Begin
        Send CreateComObject of hoChilkatGlob
    End
    Get ComUnlockBundle Of hoChilkatGlob "Anything for 30-day trial." To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoChilkatGlob To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get Create (RefClass(cComChilkatHttp)) To hoHttp
    If (Not(IsComObjectCreated(hoHttp))) Begin
        Send CreateComObject of hoHttp
    End

    // Call the async version of the QuickGetObj method to return a task object.
    // The task object is loaded, but is in the Inert state -- meaning it is
    // not yet scheduled to run on Chilkat's background thread pool.
    Get ComQuickGetObjAsync Of hoHttp "https://stackexchange.com" To vTask
    If (IsComObject(vTask)) Begin
        Get Create (RefClass(cComChilkatTask)) To hoTask
        Set pvComObject Of hoTask To vTask
    End
    Get ComLastMethodSuccess Of hoHttp To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoHttp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Schedule the task for running on the thread pool.  This changes the task's state
    // from Inert to Live.
    Get ComRun Of hoTask To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoTask To sTemp1
        Showln sTemp1
        Send Destroy of hoTask
        Procedure_Return
    End

    // The application is now free to do anything else
    // while the HTML page is being downloaded.

    // For this example, we'll simply sleep and periodically
    // check to see if the QuickGetObjAsync if finished.
    While ((ComFinished(hoTask)) <> True)

        // Sleep 100 ms.
        Send ComSleepMs To hoTask 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:
    Get ComStatusInt Of hoTask To iTemp1
    If (iTemp1 <> 7) Begin
        Showln "Task did not complete."
        Get ComStatus Of hoTask To sTemp1
        Showln "task status: " sTemp1
        Send Destroy of hoTask
        Procedure_Return
    End

    // The synchronous call to QuickGetObj would return an HTTP response object.  To get this 
    // response object for the async call, we instantiate a new/empty HTTP response object,
    // and then load it from the completed task.
    Get Create (RefClass(cComChilkatHttpResponse)) To hoResp
    If (Not(IsComObjectCreated(hoResp))) Begin
        Send CreateComObject of hoResp
    End

    Get ComLoadTaskResult Of hoResp vTask To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoResp To sTemp1
        Showln sTemp1
        Send Destroy of hoTask
        Procedure_Return
    End

    Send Destroy of hoTask

    // Now that we have the response, we can get all of the information:

    Get ComStatusCode Of hoResp To iTemp1
    Showln "status code: " iTemp1
    Get ComHeader Of hoResp To sTemp1
    Showln "response header: " sTemp1

    // ..


End_Procedure