C# WebBrowser -> WebView2 solution

Hi Steve_PP 

It is all working ok as we don't have a new app and are using the SDK.

We are just investigating what other WebView files we need to include for the client installation and then we should be good to go with updating our clients which will be an enormous relief.

You have been extremely generous, and I cannot thank you enough.

Trish

Just to complete this thread, the issue with new app keys is that you can only create 2 without getting MYOB involved to manually activate them.

Hi Trish, sure.

        // Helper function to extract the authorization code from the URL
        private static string ExtractAuthorizationCode(string uri)
        {
            var uriObj = new Uri(uri);
            var queryParams = HttpUtility.ParseQueryString(uriObj.Query);
            return queryParams["code"];
        }

Here's the whole class:

    public static class OAuthLogin
    {
        private const string CsOAuthServer = "https://secure.myob.com/oauth2/account/authorize/";
        private const string CsOAuthScope = "CompanyFile";
        private static string _currentUri = string.Empty;

        public static async Task<string> GetAuthorizationCode(IApiConfiguration config)
        {
            // Format the URL for the OAuth server login
            string url = string.Format("{0}?client_id={1}&redirect_uri={2}&scope={3}&response_type=code",
                                       CsOAuthServer, config.ClientId, HttpUtility.UrlEncode(config.RedirectUrl), CsOAuthScope);

            // Create a new form with WebView2
            var frm = new Form();
            var webView2 = new WebView2
            {
                Dock = DockStyle.Fill
            };
            frm.Controls.Add(webView2);

            // Set up a TaskCompletionSource to signal when the form can close
            var tcs = new TaskCompletionSource<string>();

            // Subscribe to NavigationCompleted to capture the OAuth redirect
            webView2.CoreWebView2InitializationCompleted += (sender, args) =>
            {
                if (args.IsSuccess)
                {
                    // Navigate to the OAuth login URL
                    webView2.CoreWebView2.Navigate(url);
                }
            };

            // Capture the URL in NavigationStarting
            webView2.NavigationStarting += (sender, args) =>
            {
                // Store the URI when navigation starts
                _currentUri = args.Uri;
            };

            // Use NavigationCompleted to check if the URI contains the authorization code
            webView2.NavigationCompleted += (sender, args) =>
            {
                if (_currentUri.Contains("code="))
                {
                    // Extract the authorization code from the URL
                    string code = ExtractAuthorizationCode(_currentUri);

                    // Signal the TaskCompletionSource that the form can close with the code
                    tcs.SetResult(code);

                    // Close the form
                    frm.Invoke((MethodInvoker)(() => frm.Close()));
                }
            };

            // Initialize WebView2 control asynchronously
            await webView2.EnsureCoreWebView2Async(null);

            frm.Size = new Size(800, 600);
            frm.Show();

            // Wait until the TaskCompletionSource is signaled (form is closed)
            string authCode = await tcs.Task;

            return authCode;

        }

        // Helper function to extract the authorization code from the URL
        private static string ExtractAuthorizationCode(string uri)
        {
            var uriObj = new Uri(uri);
            var queryParams = HttpUtility.ParseQueryString(uriObj.Query);
            return queryParams["code"];
        }

    }

That all looks fine. Have you tried cleaning the solution? Build | Clean solution 

I needed to install MicrosoftEdgeWebView2RuntimeInstallerX64

Here's some other info that may be useful. From my reading (not testing,) WebBrowser, available in .NET, runs in IE7 mode by default. There are some reg keys you can use to push it up to IE11 but MYOB have said even that won't be supported soon, so switching to WebView2 makes sense.

After you make the original GET request, after a lot of bouncing around (about 5 calls, which you can see if you put a break on webView2.NavigationStarting in my code) you end up with a return result that includes your chosen redirect URL, e.g. http://desktop, and a bunch of query parameters that include the code you need to POST to get the access tokens. I'm guessing that 'bouncing' now won't happen if you're not using a modern browser (maybe the issue is javascript related?)

The return URL (if using http://desktop) will definitely result in a navigation error because it doesn't point to a valid resource, but is serves the purpose of presenting the code, which you can extract for the next step. I don't remember seeing a page navigation error with the WebBrowser control, probably because the form was closed before it was rendered. With my code, you do get a flash of the error page before the form automatically closes.

I guess if you can't find suitable browser to invoke within your app, you could start an external browser to make the GET request, and make the redirect URL something like http://localhost:1234 and set up a port listener in your app to retrieve the result. Or if that's also a problem, simply provide instructions for the user to copy and paste the redirect URL back into your app so you can extract the code.