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.NET Core C#

Quickbooks OAuth2 in a Desktop App

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Demonstrates how to get a QuickBooks OAuth2 access token from a desktop application or script.

Chilkat .NET Core C# Downloads

.NET Core C#
bool success = false;

// To further clarify, see OAuth 2.0 Authorization Flow

// ------------------------------------------------------------------------------------------------
// IMPORTANT: You first need to define an App in the Quickbooks Developer Dashboard.
// See How to Create an App in QuickBooks Developer Dashboard
// ------------------------------------------------------------------------------------------------

// This example is for desktop applicatons (it is not for code that runs on a web server).
// You'll need to add a line (or a few lines of code) to popup a web browser that navigates to a URL.

// This is the way to initially obtain the OAuth2 access token.  Afterwards it can be 
// repeatedly refreshed without user interaction, as shown in this example: Refresh Quickbooks OAuth2 Access Token.

Chilkat.OAuth2 oauth2 = new Chilkat.OAuth2();

// QuickBooks OAuth2 allows for an "http://localhost:<portNumber>/" callback URL for sandbox testing,
// but not for production.

// In production, your applicaton must use your own public web server as an intermediate
// to receive and forward the redirect to localhost.
// See Using Your Web Server as an Intermediary for OAuth2 Redirect to localhost

oauth2.AppCallbackUrl = "https://yourwebserver.com/OAuth2.php";
oauth2.ListenPort = 3017;

oauth2.AuthorizationEndpoint = "https://appcenter.intuit.com/connect/oauth2";
oauth2.TokenEndpoint = "https://oauth.platform.intuit.com/oauth2/v1/tokens/bearer";

// Replace these with actual values.
oauth2.ClientId = "QUICKBOOKS-CLIENT-ID";
oauth2.ClientSecret = "QUICKBOOKS-CLIENT-SECRET";
oauth2.UseBasicAuth = true;
oauth2.CodeChallenge = false;

// Indicate the desired access.  Possible scopes that can appear in the list are:
// com.intuit.quickbooks.accounting:  QuickBooks Online API
// com.intuit.quickbooks.payment:  QuickBooks Payments API
// openid:  OpenID Connect processing
// profile:  user's given and family names
// email:  user's email address
// phone:  user's phone number
// address:  user's physical address
oauth2.Scope = "com.intuit.quickbooks.accounting";

// Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
string url = oauth2.StartAuth();
if (oauth2.LastMethodSuccess == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

Debug.WriteLine("url = " + url);

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
success = oauth2.LaunchBrowser(url);
if (success == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

// Wait for the user to approve or deny authorization in the browser.
int numMsWaited = 0;
while ((numMsWaited < 90000) && (oauth2.AuthFlowState < 3)) {
    oauth2.SleepMs(100);
    numMsWaited = numMsWaited + 100;
}

// If the browser does not respond within the specified time, AuthFlowState will be:
// 
// 1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
// 2: Waiting for Final Response – The thread is awaiting the final access token response.
// In either case, cancel the background task initiated by StartAuth.

if (oauth2.AuthFlowState < 3) {
    oauth2.Cancel();
    Debug.WriteLine("No response from the browser!");
    return;
}

// Check AuthFlowState to determine if authorization was granted, denied, or failed:
// 
// 3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
// 4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
// 5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

if (oauth2.AuthFlowState == 5) {
    Debug.WriteLine("OAuth2 failed to complete.");
    Debug.WriteLine(oauth2.FailureInfo);
    return;
}

if (oauth2.AuthFlowState == 4) {
    Debug.WriteLine("OAuth2 authorization was denied.");
    Debug.WriteLine(oauth2.AccessTokenResponse);
    return;
}

if (oauth2.AuthFlowState != 3) {
    Debug.WriteLine("Unexpected AuthFlowState:" + Convert.ToString(oauth2.AuthFlowState));
    return;
}

// Save the full JSON access token response to a file.
Chilkat.StringBuilder sbJson = new Chilkat.StringBuilder();
sbJson.Append(oauth2.AccessTokenResponse);
sbJson.WriteFile("qa_data/tokens/qb-access-token.json","utf-8",false);

// The full JSON received looks like this:
// {
//   "expires_in": 3600,
//   "x_refresh_token_expires_in": 8726400,
//   "refresh_token": "L011546037639r ... 3vR2DrbOmg0Sdagw",
//   "access_token": "eyJlbmMiOiJBMTI4Q0 ... oETJEMbeggg",
//   "token_type": "bearer"
// }

Debug.WriteLine("OAuth2 authorization granted!");
Debug.WriteLine("Access Token = " + oauth2.AccessToken);

// Get the realmId if needed...
// See About the QuickBooks REST API Realm ID, also known as Company ID
string realmId = oauth2.GetRedirectRequestParam("realmId");
if (oauth2.LastMethodSuccess == true) {
    Debug.WriteLine("realmId: " + realmId);
}
else {
    Debug.WriteLine("No realmId was provided.");
}