Change Webbrowser background color in WPF - html

Question

I have webbrowser control in my xaml code and i want to change it's document's background color.
<WebBrowser Source="http://google.com" x:Name="IE" Navigated="IE_Navigated" />
private void IE_Navigated(object sender, NavigationEventArgs e)
{
HtmlDocument document = (HtmlDocument)IE.Document;
var color = System.Drawing.Color.Black;
document.BackColor = color;
}
it's not working;

Answer 1

The reason why it doesn't work is because you have a mix of WPF WebBrowser and WinForms WebBrowser and they are not compatible.
Your XAML is creating a WPF WebBrowser, but in the Navigated event, you are casting IE.Document as HtmlDocument, which is the type for the WinForms WebBrowser. Consequently that cast will fail.
Even if you change it to work, there is a further problem in that the Navigated event is fired once downloading has started, not after it has finished (as documented on MSDN). The WPF WebBrowser does not have a DocumentCompleted event like the WinForms WebBrowser does.
If you want this functionality in a WPF application, a simple approach is to use the WinForms WebBrowser instead of the WPF version. This is done by hosting it in a WindowsFormsHost as shown below:
<wfi:WindowsFormsHost Name="host" />
You have to include a reference to System.Windows.Forms (which you probably already have) and WindowsFormsIntegration, and then define the namespace as:
xmlns:wfi="clr-namespace:System.Windows.Forms.Integration;assembly=WindowsFormsIntegration"
And in the code-behind:
webBrowser = new System.Windows.Forms.WebBrowser();
host.Child = webBrowser;
Then to navigate:
webBrowser.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(webBrowser_DocumentCompleted);
webBrowser.Navigate("http://google.com");
Then to set the background to black, you would do so on the body, like this:
void webBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
HtmlDocument document = (HtmlDocument)webBrowser.Document;
document.Body.Style = "background-color:black";
}
I have tested this and it works.