CefSharp make a POST web api call Win Forms c#

Question

I want to use CefSharp to make a POST web api call in Win Forms c#.

I have Basic Authentication for my POST request. But if I run the code I get the error on line IFrame frame = browser.GetMainFrame(); :

Browser is not yet initialized. Use the IsBrowserInitializedChanged event and check the IsBrowserInitialized property to determine when the browser has been intialized.

Is there a way to resolve the same?

Following is my code:

public partial class Form1 : Form
{

    ChromiumWebBrowser browser = null;
    public Form1()
    {
        InitializeComponent();

        Cef.Initialize(new CefSettings());
        browser = new ChromiumWebBrowser("http://ctstest.azurewebsites.net/api/default");
        this.Controls.Add(browser);
        browser.Dock = DockStyle.Fill;

        PostTest.Navigate(browser, "http://ctstest.azurewebsites.net/api/default", null, "application/json");

    }
}

public static class PostTest
    {
    public static void Navigate(this IWebBrowser browser, string url, byte[] postDataBytes, string contentType)
    {
        IFrame frame = browser.GetMainFrame();
        IRequest request = frame.CreateRequest();

        request.Url = url;
        request.Method = "POST";

        request.InitializePostData();
        var element = request.PostData.CreatePostDataElement();
        element.Bytes = postDataBytes;
        request.PostData.AddElement(element);

        NameValueCollection headers = new NameValueCollection();
        headers.Add("Content-Type", contentType);
        request.Headers = headers;

        frame.LoadRequest(request);

        frame.GetTextAsync().ContinueWith(taskHtml =>
        {
            var html = taskHtml.Result;
            System.Windows.Forms.MessageBox.Show(html);
        });

        string script = string.Format("document.documentElement.outerHTML;");
        frame.EvaluateScriptAsync(script).ContinueWith(x =>
        {
            var response = x.Result;

            if (response.Success && response.Result != null)
            {
                var fullhtml = response.Result;
                System.Windows.Forms.MessageBox.Show(fullhtml.ToString());
            }
        });
    }

}
}

Thanks.

Answer 1

Well like the error message is telling you, you should check if the browser is already initialized.

I don't know the implementation of the class ChromiumWebBrowser but I would try to first navigate to the desired url

browser.navigate(yourUrl);

and maybe check if the browser has already navigated to your url by subscribing to the event IsBrowserInitialized before calling browser.GetMainFrame() (like amaitland mentioned)