WPF WebBrowser control - how to suppress script errors?

Here is a C# routine that is capable of putting WPF's WebBrowser in silent mode. You can't call it at WebBrowser initialization as it 's too early, but instead after navigation occured. Here is a WPF sample app with a wbMain WebBrowser component:

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
        wbMain.Navigated += new NavigatedEventHandler(wbMain_Navigated);
    }

    void wbMain_Navigated(object sender, NavigationEventArgs e)
    {
        SetSilent(wbMain, true); // make it silent
    }

    private void button1_Click(object sender, RoutedEventArgs e)
    {
        wbMain.Navigate(new Uri("... some url..."));
    }
}


public static void SetSilent(WebBrowser browser, bool silent)
{
    if (browser == null)
        throw new ArgumentNullException("browser");

    // get an IWebBrowser2 from the document
    IOleServiceProvider sp = browser.Document as IOleServiceProvider;
    if (sp != null)
    {
        Guid IID_IWebBrowserApp = new Guid("0002DF05-0000-0000-C000-000000000046");
        Guid IID_IWebBrowser2 = new Guid("D30C1661-CDAF-11d0-8A3E-00C04FC9E26E");

        object webBrowser;
        sp.QueryService(ref IID_IWebBrowserApp, ref IID_IWebBrowser2, out webBrowser);
        if (webBrowser != null)
        {
            webBrowser.GetType().InvokeMember("Silent", BindingFlags.Instance | BindingFlags.Public | BindingFlags.PutDispProperty, null, webBrowser, new object[] { silent });
        }
    }
}


[ComImport, Guid("6D5140C1-7436-11CE-8034-00AA006009FA"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
private interface IOleServiceProvider
{
  [PreserveSig]
  int QueryService([In] ref Guid guidService, [In] ref Guid riid, [MarshalAs(UnmanagedType.IDispatch)] out object ppvObject);
}

Thought it'd be relevant to add here. There is another option to get to the WPF WebBrowser's underlying WebBorwser ActiveX Control and its otherwise inaccessible methods and events. I just discovered it a few days ago. It's very simple and doesn't require initial navigation on WB:

dynamic activeX = this.WB.GetType().InvokeMember("ActiveXInstance",
                    BindingFlags.GetProperty | BindingFlags.Instance | BindingFlags.NonPublic,
                    null, this.WB, new object[] { });

activeX.Silent = true;

Of course, there's a chance this method may not work in future version of the Framework, but so is true about any other undocumented method. So far, it's been there since .NET 3.0. More details with a working code sample here.


Thanks to Simon Mourier for elegant way to solve this problem. I made a little improvement and encapsulated Simon's solution into attached property.

In my application I use WebBrowser control databounded to viewmodel, the webbrowser might be hidden on inactive TabItem, so I have to check that it has been Loaded and Navigated before setting javascript errors silent. And of cource this setting should be done just once, so after setting I release hooked events.

XAML Code:

<TabControl xmlns:b="clr-namespace:MyApplication.Behaviors">
  <TabItem Header="foo">...</TabItem>
  <TabItem Header="Google map">
    <WebBrowser b:BindableSource="{Binding Path=MapUrl}"
                b:DisableJavascriptErrors="True" />
  </TabItem>
</TabControl>

Behavior code:

using System;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;

namespace MyApplication.Behaviors
{
    public class WebBrowserBehavior
    {
        private static readonly Type OwnerType = typeof (WebBrowserBehavior);

        #region BindableSource

        public static readonly DependencyProperty BindableSourceProperty =
            DependencyProperty.RegisterAttached(
                "BindableSource", 
                typeof(string), 
                OwnerType, 
                new UIPropertyMetadata(OnBindableSourcePropertyChanged));

        [AttachedPropertyBrowsableForType(typeof(WebBrowser))]
        public static string GetBindableSource(DependencyObject obj)
        {
            return (string)obj.GetValue(BindableSourceProperty);
        }

        [AttachedPropertyBrowsableForType(typeof(WebBrowser))]
        public static void SetBindableSource(DependencyObject obj, string value)
        {
            obj.SetValue(BindableSourceProperty, value);
        }

        public static void OnBindableSourcePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var browser = d as WebBrowser;
            if (browser == null) return;

            browser.Source = (e.NewValue != null) ? new Uri(e.NewValue.ToString()) : null;
        }

        #endregion

        #region DisableJavascriptErrors

        #region SilentJavascriptErrorsContext (private DP)

        private static readonly DependencyPropertyKey SilentJavascriptErrorsContextKey =
            DependencyProperty.RegisterAttachedReadOnly(
                "SilentJavascriptErrorsContext",
                typeof (SilentJavascriptErrorsContext),
                OwnerType,
                new FrameworkPropertyMetadata(null));

        private static void SetSilentJavascriptErrorsContext(DependencyObject depObj, SilentJavascriptErrorsContext value)
        {
            depObj.SetValue(SilentJavascriptErrorsContextKey, value);
        }

        private static SilentJavascriptErrorsContext GetSilentJavascriptErrorsContext(DependencyObject depObj)
        {
            return (SilentJavascriptErrorsContext) depObj.GetValue(SilentJavascriptErrorsContextKey.DependencyProperty);
        }

        #endregion

        public static readonly DependencyProperty DisableJavascriptErrorsProperty =
            DependencyProperty.RegisterAttached(
                "DisableJavascriptErrors",
                typeof (bool),
                OwnerType,
                new FrameworkPropertyMetadata(OnDisableJavascriptErrorsChangedCallback));

        [AttachedPropertyBrowsableForType(typeof(WebBrowser))]
        public static void SetDisableJavascriptErrors(DependencyObject depObj, bool value)
        {
            depObj.SetValue(DisableJavascriptErrorsProperty, value);
        }

        [AttachedPropertyBrowsableForType(typeof(WebBrowser))]
        public static bool GetDisableJavascriptErrors(DependencyObject depObj)
        {
            return (bool)depObj.GetValue(DisableJavascriptErrorsProperty);
        }

        private static void OnDisableJavascriptErrorsChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var webBrowser = d as WebBrowser;
            if (webBrowser == null) return;
            if (Equals(e.OldValue, e.NewValue)) return;

            var context = GetSilentJavascriptErrorsContext(webBrowser);
            if (context != null) {
                context.Dispose();
            }

            if (e.NewValue != null) {
                context = new SilentJavascriptErrorsContext(webBrowser);
                SetSilentJavascriptErrorsContext(webBrowser, context);
            }
            else {
                SetSilentJavascriptErrorsContext(webBrowser, null);
            }
        }

        private class SilentJavascriptErrorsContext : IDisposable
        {
            private bool? _silent; 
            private readonly WebBrowser _webBrowser;


            public SilentJavascriptErrorsContext(WebBrowser webBrowser)
            {
                _silent = new bool?();

                _webBrowser = webBrowser;
                _webBrowser.Loaded += OnWebBrowserLoaded;
                _webBrowser.Navigated += OnWebBrowserNavigated;
            }

            private void OnWebBrowserLoaded(object sender, RoutedEventArgs e)
            {
                if (!_silent.HasValue) return;

                SetSilent();
            }

            private void OnWebBrowserNavigated(object sender, NavigationEventArgs e)
            {
                var webBrowser = (WebBrowser)sender;

                if (!_silent.HasValue) {
                    _silent = GetDisableJavascriptErrors(webBrowser);
                }

                if (!webBrowser.IsLoaded) return;

                SetSilent();
            }

            /// <summary>
            /// Solution by Simon Mourier on StackOverflow
            /// http://stackoverflow.com/a/6198700/741414
            /// </summary>
            private void SetSilent()
            {
                _webBrowser.Loaded -= OnWebBrowserLoaded;
                _webBrowser.Navigated -= OnWebBrowserNavigated;

                // get an IWebBrowser2 from the document
                var sp = _webBrowser.Document as IOleServiceProvider;
                if (sp != null)
                {
                    var IID_IWebBrowserApp = new Guid("0002DF05-0000-0000-C000-000000000046");
                    var IID_IWebBrowser2 = new Guid("D30C1661-CDAF-11d0-8A3E-00C04FC9E26E");

                    object webBrowser2;
                    sp.QueryService(ref IID_IWebBrowserApp, ref IID_IWebBrowser2, out webBrowser2);
                    if (webBrowser2 != null)
                    {
                        webBrowser2.GetType().InvokeMember(
                            "Silent",
                            BindingFlags.Instance | BindingFlags.Public | BindingFlags.PutDispProperty,
                            null,
                            webBrowser2,
                            new object[] { _silent });
                    }
                }
            }

            [ComImport, Guid("6D5140C1-7436-11CE-8034-00AA006009FA"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
            private interface IOleServiceProvider
            {
                [PreserveSig]
                int QueryService([In] ref Guid guidService, [In] ref Guid riid, [MarshalAs(UnmanagedType.IDispatch)] out object ppvObject);
            }

            public void Dispose()
            {
                if (_webBrowser != null) {
                    _webBrowser.Loaded -= OnWebBrowserLoaded;
                    _webBrowser.Navigated -= OnWebBrowserNavigated;
                }
            }
        }

        #endregion

    }
}