VB.NET

HttpPostJson2Async Example

Demonstrates use of the HttpPostJson2Async method. VB.NET

Dim success As Boolean = False

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

' See PostJson2 Example for the synchronous equivalent of this example.

Dim http As New Chilkat.Http

' Sends a POST equivalent to the following CURL command:

' curl -X POST https://sandbox.plaid.com/institutions/get \
'   -H 'content-type: application/json' \
'   -d '{
'     "client_id": String,
'     "secret":String,
'     "count": Number,
'     "offset": Number
'   }'

' Suppress some default headers that would automatically added..
http.AcceptCharset = ""
http.UserAgent = ""
http.AcceptLanguage = ""
http.AllowGzip = False

Dim jsonBody As String = "{""client_id"": ""PLAID_CLIENT_ID"", ""secret"":""PLAID_SECRET"", ""count"": 10, ""offset"": 0}"
Dim task As Chilkat.Task = http.PostJson2Async("https://sandbox.plaid.com/institutions/get","application/json",jsonBody)
If (http.LastMethodSuccess = False) Then
    Debug.WriteLine(http.LastErrorText)
    Exit Sub
End If


' Start the background task.
success = task.Run()
If (Not success) Then
    Debug.WriteLine(task.LastErrorText)

    Exit Sub
End If


' The application is now free to do anything else
' while the HTTP POST is in progress

' For this example, we'll simply sleep and periodically
' check to see if the HTTP POST is finished.  
While task.Finished <> True
    ' Sleep 100 ms.
    task.SleepMs(100)
End While

' When we get here, the task is either finished successfully or not, or was canceled/aborted.

' 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 getting the result of the underlying method call.
' A task status of 7 indicates completion.
If (task.StatusInt <> 7) Then
    Debug.WriteLine("Task did not complete.")
    Debug.WriteLine("task status: " & task.Status)

    Exit Sub
End If


' When called synchronously, the PostJson2 method returns an HTTP response object,
' unless the method failed and there was no response to be had.
' Check to see if PostJson2 method failed (and thus there is no response object).
If (task.TaskSuccess = False) Then
    Debug.WriteLine("The underlying task failed, and there is no HTTP response object.")
    Debug.WriteLine("The LastErrorText for the underlying method call is:")
    Debug.WriteLine(task.ResultErrorText)

    Exit Sub
End If


' To get the HTTP response object, create a new instance and load it with the result from the task.
Dim resp As New Chilkat.HttpResponse
resp.LoadTaskResult(task)


Dim statusCode As Integer = resp.StatusCode
Debug.WriteLine("Response status code = " & statusCode)

' Examine the JSON response..
Dim json As New Chilkat.JsonObject
json.Load(resp.BodyStr)
json.EmitCompact = False
Debug.WriteLine("JSON Response Body:")
Debug.WriteLine(json.Emit())