The example you provided使用WinFormsBrowserView，它只存在于DotNetBrowser的早期版本（1.x）中。
对于当前版本，请使用其文档中提供的示例。您需要创建一个IEngine示例，使用该示例创建一个IBrowser示例，并通过browserView.InitializeFrom(browser);将IBrowser传递给BrowserView。
示例取自documentation for DotNetBrowser：

using System.Windows.Forms;
using DotNetBrowser.Browser;
using DotNetBrowser.Engine;
using DotNetBrowser.WinForms;

namespace Embedding.WinForms
{
    /// <summary>
    ///     This example demonstrates how to embed DotNetBrowser
    ///     into a Windows Forms application.
    /// </summary>
    public partial class Form1 : Form
    {
        private const string Url = "https://html5test.com/";
        private readonly IBrowser browser;
        private readonly IEngine engine;

        public Form1()
        {
            // Create the Windows Forms BrowserView control.
            BrowserView browserView = new BrowserView
            {
                Dock = DockStyle.Fill
            };

            // Create and initialize the IEngine instance.
            EngineOptions engineOptions = new EngineOptions.Builder
            {
                RenderingMode = RenderingMode.HardwareAccelerated
            }.Build();
            engine = EngineFactory.Create(engineOptions);

            // Create the IBrowser instance.
            browser = engine.CreateBrowser();

            InitializeComponent();

            // Add the BrowserView control to the Form.
            Controls.Add(browserView);
            FormClosed += Form1_FormClosed;

            // Initialize the Windows Forms BrowserView control.
            browserView.InitializeFrom(browser);
            browser.Navigation.LoadUrl(Url);
        }

        private void Form1_FormClosed(object sender, FormClosedEventArgs e)
        {
            browser?.Dispose();
            engine?.Dispose();
        }
    }
}