How do I suppress script errors when using the WPF WebBrowser control?

I've also found an interesting way to disable JavaScript errors. But you need to use at least .Net Framework 4.0 because of using elegant dynamic type.

You need to subscribe to the LoadCompleted event of the WebBrowser element:

<WebBrowser x:Name="Browser" 
            LoadCompleted="Browser_OnLoadCompleted" />

After that you need to write an event handler that looks like below:

    void Browser_OnLoadCompleted(object sender, NavigationEventArgs e)
    {
        var browser = sender as WebBrowser;

        if (browser == null || browser.Document == null)
            return;

        dynamic document = browser.Document;

        if (document.readyState != "complete")
            return;

        dynamic script = document.createElement("script");
        script.type = @"text/javascript";
        script.text = @"window.onerror = function(msg,url,line){return true;}";
        document.head.appendChild(script);
    }

The problem here is that the WPF WebBrowser did not implement this property as in the 2.0 control.

Your best bet is to use a WindowsFormsHost in your WPF application and use the 2.0's WebBrowser property: SuppressScriptErrors. Even then, you will need the application to be full trust in order to do this.

Not what one would call ideal, but it's pretty much the only option currently.

Here is a solution i just made with reflection. Solves the issue :) I run it at the Navigated event, as it seems the activeX object is not available until then.

What it does is set the .Silent property on the underlying activeX object. Which is the same as the .ScriptErrorsSuppressed property which is the Windows forms equivalent.

 public void HideScriptErrors(WebBrowser wb, bool Hide) {
    FieldInfo fiComWebBrowser = typeof(WebBrowser).GetField("_axIWebBrowser2", BindingFlags.Instance | BindingFlags.NonPublic);
    if (fiComWebBrowser == null) return;
    object objComWebBrowser = fiComWebBrowser.GetValue(wb);
    if (objComWebBrowser == null) return;
    objComWebBrowser.GetType().InvokeMember("Silent", BindingFlags.SetProperty, null, objComWebBrowser, new object[] { Hide });
 }

A better version that can be run anytime and not after the .Navigated event:

public void HideScriptErrors(WebBrowser wb, bool hide) {
    var fiComWebBrowser = typeof(WebBrowser).GetField("_axIWebBrowser2", BindingFlags.Instance | BindingFlags.NonPublic);
    if (fiComWebBrowser == null) return;
    var objComWebBrowser = fiComWebBrowser.GetValue(wb);
    if (objComWebBrowser == null) {
        wb.Loaded += (o, s) => HideScriptErrors(wb, hide); //In case we are to early
        return;
    }
    objComWebBrowser.GetType().InvokeMember("Silent", BindingFlags.SetProperty, null, objComWebBrowser, new object[] { hide });
}

If any issues with the second sample, try swapping wb.Loaded with wb.Navigated.

Just found from another question, this is elegant and works great.

dynamic activeX = this.webBrowser1.GetType().InvokeMember("ActiveXInstance",
                BindingFlags.GetProperty | BindingFlags.Instance | BindingFlags.NonPublic,
                null, this.webBrowser1, new object[] { });

activeX.Silent = true;