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Objective-C

PayPal - Generate Invoice Number

See more PayPal Examples

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

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

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Objective-C
#import <CkoJsonObject.h>
#import <CkoStringBuilder.h>
#import <CkoRest.h>

BOOL success = NO;

//  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)
CkoJsonObject *jsonToken = [[CkoJsonObject alloc] init];
[jsonToken LoadFile: @"qa_data/tokens/paypal.json"];

//  Build the Authorization request header field value.
CkoStringBuilder *sbAuth = [[CkoStringBuilder alloc] init];
//  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.
CkoRest *rest = [[CkoRest alloc] init];
BOOL bAutoReconnect = YES;
success = [rest Connect: @"api.sandbox.paypal.com" port: [NSNumber numberWithInt: 443] tls: YES autoReconnect: bAutoReconnect];
if (success != YES) {
    NSLog(@"%@",rest.LastErrorText);
    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.
[rest ClearAllHeaders];
[rest ClearAllQueryParams];

[rest AddHeader: @"Authorization" value: [sbAuth GetAsString]];

//  Send the POST request with an emtpy body and get the JSON response.
CkoStringBuilder *sbJsonRequest = [[CkoStringBuilder alloc] init];
CkoStringBuilder *sbJsonResponse = [[CkoStringBuilder alloc] init];
success = [rest FullRequestSb: @"POST" uriPath: @"/v1/invoicing/invoices/next-invoice-number" requestBody: sbJsonRequest responseBody: sbJsonResponse];
if (success != YES) {
    NSLog(@"%@",rest.LastErrorText);
    return;
}

CkoJsonObject *json = [[CkoJsonObject alloc] init];
json.EmitCompact = NO;
[json LoadSb: sbJsonResponse];

NSLog(@"%@%d",@"Response Status Code = ",[rest.ResponseStatusCode intValue]);

//  Did we get a 200 success response?
if ([rest.ResponseStatusCode intValue] != 200) {
    NSLog(@"%@",[json Emit]);
    NSLog(@"%@",@"Failed.");
    return;
}

//  Sample JSON response is shown below.
NSLog(@"%@",[json Emit]);
NSLog(@"%@",@"----------------------");
NSLog(@"%@%@",@"Next invoice number: ",[json StringOf: @"number"]);
NSLog(@"%@",@"success");

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

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