Is there any way to add referrer header?

[Dave-Jalpan]

I want to open a new tab instead of new window. But while doing that one of the application throws exception "Error: No referrer", as application is expecting referrer value in header. So how I can pass referrer in header from e.NewWindow while redirecting new window request to new tab?

private void CoreWebView2_NewWindowRequested(object sender, Microsoft.Web.WebView2.Core.CoreWebView2NewWindowRequestedEventArgs e)
{
    baseTemplate.AddTab(e.Uri, true); /// Creating new tab instead opening new window. 
    e.Handled = true;
}

[Symbai]

Show us the code of baseTemplate.AddTab(e.Uri, true);

[Dave-Jalpan]

Hi @Symbai

baseTemplate.AddTab is custom way to create tabs.

AddTab has following implementation

CustomTabItem newTab = (CustomTabItem)GenerateNewItem(); /// Create tab item 
newTab.Content = newTab.GenerateWebBrowser(url);  // Create WebBrowser (WebView2) and attach to newly created tab item
currentTabControl.AddTab(newTab, isSelected);  // Attach new tab item to tab control. 

[Symbai]

I guess its because you create a new webview2 and visit the url (which then has no referrer). No tested by you can try using the NewWindow property on the NewWindowRequested event to obtain the webview2 and use this instead of creating a new one. Otherwise use the GetDeferral method, listen to WebResourceRequested event, obtain the headers. Create a new tab with a new webview2 control, listen to its WebResourceRequested event and then set the headers to the previously obtained headers. I'm just not sure if WebResourceRequested would get raised before or after NewWindowRequested event raises.

Anyway to answer your original question, changing http header is done by WebResourceRequested event.

[Dave-Jalpan]

@Symbai

Sorry, but is there any code sample which I can follow?
Which opens in new tab rather new window and maintain headers.

[ukandrewc]

@Symbai @Dave-Jalpan If you use GetDeferral, you won't need WebResourceRequested as there will be a referrer header.

@Dave-Jalpan You've already had a sample here: #873

[Dave-Jalpan]

@ukandrewc
As mentioned when I converted your code I was not able to get newwindow deferrer
So please correct me, and explain how to do it.

[ukandrewc]

@Dave-Jalpan Sorry, I can't help any more, I did answer that question, but I'm very rusty on C++, so can't help with that.

[Dave-Jalpan]

@ukandrewc

Is this interpretation correct from vb to c#

Friend Deferral As CoreWebView2Deferral
Friend EventArgs As CoreWebView2NewWindowRequestedEventArgs
as

internal Microsoft.Web.WebView2.Core.CoreWebView2Deferral Deferral;
internal Microsoft.Web.WebView2.Core.CoreWebView2NewWindowRequestedEventArgs EventArgs;

and Dim Browser As New MyWebView2
as

Microsoft.Web.WebView2.Wpf.WebView2 Browser = new Microsoft.Web.WebView2.Wpf.WebView2();

if so then i am not able to set deferral

Browser.Deferral = = e.GetDeferral;

[ukandrewc]

@Dave-Jalpan Internals are correct but MyWebView2, needs to be your own inherited class

internal partial class MyWebView2 : WebView2
{
    internal Global.Microsoft.Web.WebView2.Core.CoreWebView2Deferral Deferral;
    internal Global.Microsoft.Web.WebView2.Core.CoreWebView2NewWindowRequestedEventArgs EventArgs;
}

[Dave-Jalpan]

@ukandrewc
How I can register close request event for newly open window from CoreWebView2_NewWindowRequested
I am having difficulty to handle newly open window.

private void CoreWebView2_NewWindowRequested(object sender, Microsoft.Web.WebView2.Core.CoreWebView2NewWindowRequestedEventArgs e)
        {
  // e.NewWindow is null
            e.NewWindow.WindowCloseRequested += NewWindow_WindowCloseRequested;
}

[jschroedl]

The NewWindowRequested notification is simply to let your code know that the web page wants a new window. If you take over the processing, it's up to you to create that new window containing a WebView2 and have that new WV2 pick up the navigation using the deferral. So, it's up to you to create a window and hook up its close event.

[Dave-Jalpan]

@joshholmes

Usually I handled all new window request to open new tab (WebView2). But one of the website need header referrer.
So for based on suggestions I have written following code but still no luck
Any suggestion or correction ???

public class MyWebView2 : WebView2
    {
        internal Microsoft.Web.WebView2.Core.CoreWebView2Deferral Deferral;
        internal Microsoft.Web.WebView2.Core.CoreWebView2NewWindowRequestedEventArgs EventArgs;
    }

public MyWebView2 Browser;

private void CoreWebView2_NewWindowRequested(object sender, Microsoft.Web.WebView2.Core.CoreWebView2NewWindowRequestedEventArgs e)
        {

            if(e.Uri.ToUpper().Contains(vURL.ToUpper()))  // Check URL match 
            {
                Browser = GenerateNewWindowWebBrowser();  // Create New MyWebView2 (to maintain header values)
                Browser.Deferral = e.GetDeferral();
                Browser.EventArgs = e;
            }
            else         
            {
               baseTemplate.AddTab(e.Uri, true); // Existing working new tab webView2 creation (using url string) (without extended MyWebView2)
                e.Handled = true;
            }

public MyWebView2 GenerateNewWindowWebBrowser()
        {
            try
            {
                WebView2 = new MyWebView2();
                browserWorker.ProgressChanged += new ProgressChangedEventHandler(BrowserWorker_ProgressChange);
                browserWorker.DoWork += new DoWorkEventHandler(BrowserWorker_DoWork);
                browserWorker.WorkerReportsProgress = true;
                WebView2.Source = new System.Uri("https://www.google.com");
                WebView2.CoreWebView2InitializationCompleted += WebView2_NewWindowInitialized;  
                WebView2.NavigationCompleted += webBrowser_LoadCompleted;
            }
            catch (Exception ex)
            {
                LoggedExceptionHandling.LogExceptionHandling("Unable to generate web browser", "CustomTabItem.GenerateNewWindowWebBrowser", ex);
            }
            return WebView2;
        }

It not reaching WebView2_NewWindowInitialized to complete deferral

private void WebView2_NewWindowInitialized(object sender, Microsoft.Web.WebView2.Core.CoreWebView2InitializationCompletedEventArgs e)
        {
            WebView2.CoreWebView2.NewWindowRequested += CoreWebView2_NewWindowRequested;

            if (e.IsSuccess)
            {
                // Was deferral set in previous instance?
                if (WebView2.Deferral != null)
                {
                    // Set this instance, complete NewWindowRequested and clear deferral

                    CustomTabItem newTab = (CustomTabItem)baseTemplate.GenerateNewItem();
                    newTab.Content = Browser;
                    baseTemplate.currentTabControl.AddTab(newTab, true);

                    WebView2.EventArgs.NewWindow = Browser.CoreWebView2; //Source.CoreWebView2;
                    WebView2.Deferral.Complete();
                    WebView2.Deferral = null;
                    WebView2.EventArgs = null;
                }
            }

        }