using (var browser = new MechanizeBrowser(new AngleSharpParser()))
{
}

using (var browser = new MechanizeBrowser())
{
    var page = await browser.NavigateAsync("https://www.google.com/");
    if (page.IsHtml)
    {
        var form = page.Forms["f"];
        var queryfield = form.FindControl<ScalarControl>("q");
        queryfield.Value = "Mechanize.NET";

        var newpage = await form.SubmitForm();
        var contents = newpage.Document;
        // Collect the Results from contents.
    }
}