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VB.NET

CardConnect Void

See more CardConnect Examples

Demonstrates how to send a CardConnect void request.
The void service cancels a transaction that is in either "Authorized" or "Queued for Capture" status.. ...

See https://developer.cardconnect.com/cardconnect-api#void

Chilkat VB.NET Downloads

VB.NET
Dim success As Boolean = False

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

Dim http As New Chilkat.Http

http.BasicAuth = True
http.Login = "API_USERNAME"
http.Password = "API_PASSWORD"

' Build and send the following JSON:

' The "retref" is the value returned in the JSON response for the Authorization request.

' {
'     "retref":"112989260941",
'     "merchid":"MERCHANT_ID"
' }

Dim json As New Chilkat.JsonObject
json.UpdateString("retref","112989260941")
json.UpdateString("merchid","MERCHANT_ID")

Dim url As String = "https://<site>.cardconnect.com:<port>/cardconnect/rest/void"

Dim resp As New Chilkat.HttpResponse
success = http.HttpStr("PUT",url,json.Emit(),"utf-8","application/json",resp)
If (success = False) Then
    Debug.WriteLine(http.LastErrorText)
    Exit Sub
End If


' A response status of 200 indicates potential success.  The JSON response body
' must be examined to determine if it was truly successful or an error.
Debug.WriteLine("response status code = " & resp.StatusCode)

Dim jsonResp As New Chilkat.JsonObject
jsonResp.Load(resp.BodyStr)
jsonResp.EmitCompact = False

Debug.WriteLine("response JSON:")
Debug.WriteLine(jsonResp.Emit())

' A successful response looks like this:

' {
'   "authcode": "REVERS",
'   "respproc": "FNOR",
'   "amount": "0.00",
'   "resptext": "Approval",
'   "currency": "USD",
'   "retref": "112989260941",
'   "respstat": "A",
'   "respcode": "00",
'   "merchid": "496160873888"
' }

' Use this online tool to generate parsing code from sample JSON: 
' Generate Parsing Code from JSON

Dim authcode As String = jsonResp.StringOf("authcode")
Dim respproc As String = jsonResp.StringOf("respproc")
Dim amount As String = jsonResp.StringOf("amount")
Dim resptext As String = jsonResp.StringOf("resptext")
Dim currency As String = jsonResp.StringOf("currency")
Dim retref As String = jsonResp.StringOf("retref")
Dim respstat As String = jsonResp.StringOf("respstat")
Dim respcode As String = jsonResp.StringOf("respcode")
Dim merchid As String = jsonResp.StringOf("merchid")