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Unicode C

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 Unicode C Downloads

Unicode C
#include <C_CkJsonObjectW.h>
#include <C_CkStringBuilderW.h>
#include <C_CkRestW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObjectW jsonToken;
    HCkStringBuilderW sbAuth;
    HCkRestW rest;
    BOOL bAutoReconnect;
    HCkStringBuilderW sbJsonRequest;
    HCkStringBuilderW sbJsonResponse;
    HCkJsonObjectW json;

    success = 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)
    jsonToken = CkJsonObjectW_Create();
    CkJsonObjectW_LoadFile(jsonToken,L"qa_data/tokens/paypal.json");

    // Build the Authorization request header field value.
    sbAuth = CkStringBuilderW_Create();
    // token_type should be "Bearer"
    CkStringBuilderW_Append(sbAuth,CkJsonObjectW_stringOf(jsonToken,L"token_type"));
    CkStringBuilderW_Append(sbAuth,L" ");
    CkStringBuilderW_Append(sbAuth,CkJsonObjectW_stringOf(jsonToken,L"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.
    rest = CkRestW_Create();
    bAutoReconnect = TRUE;
    success = CkRestW_Connect(rest,L"api.sandbox.paypal.com",443,TRUE,bAutoReconnect);
    if (success != TRUE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkJsonObjectW_Dispose(jsonToken);
        CkStringBuilderW_Dispose(sbAuth);
        CkRestW_Dispose(rest);
        return;
    }

    // ----------------------------------------------------------------------------------------------
    // 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.
    CkRestW_ClearAllHeaders(rest);
    CkRestW_ClearAllQueryParams(rest);

    CkRestW_AddHeader(rest,L"Authorization",CkStringBuilderW_getAsString(sbAuth));

    // Send the POST request with an emtpy body and get the JSON response.
    sbJsonRequest = CkStringBuilderW_Create();
    sbJsonResponse = CkStringBuilderW_Create();
    success = CkRestW_FullRequestSb(rest,L"POST",L"/v1/invoicing/invoices/next-invoice-number",sbJsonRequest,sbJsonResponse);
    if (success != TRUE) {
        wprintf(L"%s\n",CkRestW_lastErrorText(rest));
        CkJsonObjectW_Dispose(jsonToken);
        CkStringBuilderW_Dispose(sbAuth);
        CkRestW_Dispose(rest);
        CkStringBuilderW_Dispose(sbJsonRequest);
        CkStringBuilderW_Dispose(sbJsonResponse);
        return;
    }

    json = CkJsonObjectW_Create();
    CkJsonObjectW_putEmitCompact(json,FALSE);
    CkJsonObjectW_LoadSb(json,sbJsonResponse);

    wprintf(L"Response Status Code = %d\n",CkRestW_getResponseStatusCode(rest));

    // Did we get a 200 success response?
    if (CkRestW_getResponseStatusCode(rest) != 200) {
        wprintf(L"%s\n",CkJsonObjectW_emit(json));
        wprintf(L"Failed.\n");
        CkJsonObjectW_Dispose(jsonToken);
        CkStringBuilderW_Dispose(sbAuth);
        CkRestW_Dispose(rest);
        CkStringBuilderW_Dispose(sbJsonRequest);
        CkStringBuilderW_Dispose(sbJsonResponse);
        CkJsonObjectW_Dispose(json);
        return;
    }

    // Sample JSON response is shown below.
    wprintf(L"%s\n",CkJsonObjectW_emit(json));
    wprintf(L"----------------------\n");
    wprintf(L"Next invoice number: %s\n",CkJsonObjectW_stringOf(json,L"number"));
    wprintf(L"success\n");

    // ------------------------------------------------
    // A sample JSON response:

    // 	{ 
    // 	  "number": "0003"
    // 	}


    CkJsonObjectW_Dispose(jsonToken);
    CkStringBuilderW_Dispose(sbAuth);
    CkRestW_Dispose(rest);
    CkStringBuilderW_Dispose(sbJsonRequest);
    CkStringBuilderW_Dispose(sbJsonResponse);
    CkJsonObjectW_Dispose(json);

    }