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VB.NET

PayPal - Generate Invoice Number

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Generates the next invoice number that is available to the user.

Note: This example requires Chilkat v9.5.0.65 or greater.

Chilkat VB.NET Downloads

VB.NET
Dim success As Boolean = False

' Note: Requires Chilkat v9.5.0.65 or greater.

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

' Load our previously obtained access token. (see PayPal OAuth2 Access Token)
Dim jsonToken As New Chilkat.JsonObject
jsonToken.LoadFile("qa_data/tokens/paypal.json")

' Build the Authorization request header field value.
Dim sbAuth As New Chilkat.StringBuilder
' token_type should be "Bearer"
sbAuth.Append(jsonToken.StringOf("token_type"))
sbAuth.Append(" ")
sbAuth.Append(jsonToken.StringOf("access_token"))

' Make the initial connection.
' A single REST object, once connected, can be used for many PayPal REST API calls.
' The auto-reconnect indicates that if the already-established HTTPS connection is closed,
' then it will be automatically re-established as needed.
Dim rest As New Chilkat.Rest
Dim bAutoReconnect As Boolean = True
success = rest.Connect("api.sandbox.paypal.com",443,True,bAutoReconnect)
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


' ----------------------------------------------------------------------------------------------
' The code above this comment could be placed inside a function/subroutine within the application
' because the connection does not need to be made for every request.  Once the connection is made
' the app may send many requests..
' ----------------------------------------------------------------------------------------------

' Clear the REST object of any headers or query params from previous requests.
rest.ClearAllHeaders()
rest.ClearAllQueryParams()

rest.AddHeader("Authorization",sbAuth.GetAsString())

' Send the POST request with an emtpy body and get the JSON response.
Dim sbJsonRequest As New Chilkat.StringBuilder
Dim sbJsonResponse As New Chilkat.StringBuilder
success = rest.FullRequestSb("POST","/v1/invoicing/invoices/next-invoice-number",sbJsonRequest,sbJsonResponse)
If (success <> True) Then
    Debug.WriteLine(rest.LastErrorText)
    Exit Sub
End If


Dim json As New Chilkat.JsonObject
json.EmitCompact = False
json.LoadSb(sbJsonResponse)

Debug.WriteLine("Response Status Code = " & rest.ResponseStatusCode)

' Did we get a 200 success response?
If (rest.ResponseStatusCode <> 200) Then
    Debug.WriteLine(json.Emit())
    Debug.WriteLine("Failed.")
    Exit Sub
End If


' Sample JSON response is shown below.
Debug.WriteLine(json.Emit())
Debug.WriteLine("----------------------")
Debug.WriteLine("Next invoice number: " & json.StringOf("number"))
Debug.WriteLine("success")

' ------------------------------------------------
' A sample JSON response:

' 	{ 
' 	  "number": "0003"
' 	}