VB.NET

Asynchronous HTTP SOAP 1.2 Request and Response using POST

Demonstrates a working asynchronous SOAP 1.2 request and response using POST with a live server. You may try running this example with the URLs and data provided. See http://wsf.cdyne.com/WeatherWS/Weather.asmx?op=GetCityWeatherByZIP for details.

Note: This example is correct in theory, but no longer works for live testing because the SOAP service provider (cdyne.com) has made changes or discontinued the free service.

VB.NET

' TaskCompleted callback method.
Private Sub http_OnTaskCompleted(sender As Object, args As Chilkat.TaskCompletedEventArgs) Handles http.OnTaskCompleted

    Dim completedTask As Chilkat.Task = args.Task;
        ' 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 (completedTask.StatusInt <> 7) Then
        Debug.WriteLine("Task did not complete.")
        Debug.WriteLine("task status: " & completedTask.Status)
        Exit Sub
    End If


    ' 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.
    Dim resp As New Chilkat.HttpResponse

    success = resp.LoadTaskResult(completedTask)
    If (success <> True) Then
        Debug.WriteLine(resp.LastErrorText)
        Exit Sub
    End If


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

    Debug.WriteLine("status code: " & resp.StatusCode)
    Debug.WriteLine("response header: " & resp.Header)

    Dim xmlResponse As New Chilkat.Xml
    xmlResponse.LoadXml(resp.BodyStr)
    Debug.WriteLine(xmlResponse.GetXml())
End Sub

private Sub ChilkatExample()

    Dim success As Boolean = False

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



    Dim WithEvents http As New Chilkat.Http

    Dim soapXml As New Chilkat.Xml

    soapXml.Tag = "soap12:Envelope"
    soapXml.AddAttribute("xmlns:xsi","http://www.w3.org/2001/XMLSchema-instance")
    soapXml.AddAttribute("xmlns:xsd","http://www.w3.org/2001/XMLSchema")
    soapXml.AddAttribute("xmlns:soap12","http://www.w3.org/2003/05/soap-envelope")

    soapXml.NewChild2("soap12:Body","")
    soapXml.GetChild2(0)
    soapXml.NewChild2("GetCityWeatherByZIP","")
    soapXml.GetChild2(0)
    soapXml.AddAttribute("xmlns","http://ws.cdyne.com/WeatherWS/")
    soapXml.NewChild2("ZIP","60187")
    soapXml.GetRoot2()

    Debug.WriteLine(soapXml.GetXml())

    Dim req As New Chilkat.HttpRequest
    req.HttpVerb = "POST"
    req.SendCharset = False
    req.AddHeader("Content-Type","application/soap+xml; charset=utf-8")
    req.AddHeader("SOAPAction","http://ws.cdyne.com/WeatherWS/GetCityWeatherByZIP")
    req.Path = "/WeatherWS/Weather.asmx"
    req.LoadBodyFromString(soapXml.GetXml(),"utf-8")

    http.FollowRedirects = True

    Dim task As Chilkat.Task = http.SynchronousRequestAsync("wsf.cdyne.com",80,False,req)
    If (http.LastMethodSuccess <> True) Then
        Debug.WriteLine(http.LastErrorText)
        Exit Sub
    End If


    ' Schedule the task for running on the thread pool.  This changes the task's state
    ' from Inert to Live.
    success = task.Run()
    If (success <> True) Then
        Debug.WriteLine(task.LastErrorText)

        Exit Sub
    End If


    ' The application is now free to do anything else
    ' while the HTTP request is in progress.  When the task
    ' is completed, the TaskCompleted method is called.


    ' -------------------------------------------------------------------------------
    ' The following is a general note that applies to all programming languages:
    ' -------------------------------------------------------------------------------

    ' NOTE: This is very important:  The TaskCompleted callback runs in the background thread.  
    ' (All callbacks from an async task, such as AbortCheck, PercentDone, ProgressInfo, etc. are in the background thread.) 
    ' An application that uses TaskCompleted must be very careful.  
    ' For example, user interface elements (such as labels, text boxes, etc.) may not be directly
    ' accessible from a background thread, and could crash the application if directly accessed.  Also, attempting to debug
    ' code running in a background thread from an IDE, especially an older IDE (such as VB6) is likely to crash the IDE.

End Sub