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Open Links containing pattern in different tab in CefSharp WPF

I have an application with two tabs in a tab control, each containing a CefSharp ChromiumWebBrowser. Let's call these ChromiumWebBrowsers searchBrowser and detailsBrowser.
Let's say I click a link in searchBrowser, and if that link contains the text "xrep2", I want the link to be opened in detailsBrowser, else it should be opened in searchBrowser.
In a previous version of this application, I used the WinForms web browser control. I'm rewriting the app in WPF and using CefSharp. with the WinForms it was quite simple. In the Navigating event, you do something like
private void browser_Navigating(object sender, WebBrowserNavigatingEventArgs e)
{
if (browser.StatusText.Contains("xrep2."))
{
e.Cancel = true;
detailsBrowser.Url = new Uri(browser.StatusText);
tabControl1.SelectedIndex = 1;
}
}
But when using CefSharp, it appears I have to create an event inside a LifeSpanHandler per this post with an event that fires when a target="_blank" link is clicked. I'm not super comfortable creating and subscribing to custom events, so I'd like to find an easier way to do this, but if not, I need to figure out how to subscribe a method to the event created by public event Action<string> PopupRequest; and where to put the logic (something like if(searchBrowser.Address.Contains("xrep2")) detailsBrowser.Address = X else searchBrowser.Address = X
I have the LifeSpanHandler class code below, including the PopupRequest event that is supposed to fire when a target="_blank" link is clicked, but I'm stuck at this point.
public class LifeSpanHandler : ILifeSpanHandler
{
public event Action<string> PopupRequest;
public virtual bool OnBeforePopup(IWebBrowser browserControl, string sourceUrl, string targetUrl, ref int x, ref int y, ref int width,
ref int height)
{
if (PopupRequest != null)
PopupRequest(targetUrl);
return true;
}
}

CefSharp documentcompleted

I am trying to use cefshar browser in C# winforms and need to know how I know when page completely loaded and how I can get browser document and get html elements,
I just Initialize the browser and don't know what I should do next:
public Form1()
{
InitializeComponent();
Cef.Initialize(new CefSettings());
browser = new ChromiumWebBrowser("http://google.com");
BrowserContainer.Controls.Add(browser);
browser.Dock = DockStyle.Fill;
}

CefSharp has a LoadingStateChanged event with LoadingStateChangedArgs.
LoadingStateChangedArgs has a property called IsLoading which indicates if the page is still loading.
You should be able to subscribe to it like this:
browser.LoadingStateChanged += OnLoadingStateChanged;
The method would look like this:
private void OnLoadingStateChanged(object sender, LoadingStateChangedEventArgs args)
{
if (!args.IsLoading)
{
// Page has finished loading, do whatever you want here
}
}
I believe you can get the page source like this:
string HTML = await browser.GetSourceAsync();
You'd probably need to get to grips with something like HtmlAgility to parse it, I'm not going to cover that as it's off topic.

I ended up using:
using CefSharp;
wbAuthorization.AddressChanged += OnAddressChanged;
and
private void OnAddressChanged(
object s,
AddressChangedEventArgs e)
{
if (e.Address.StartsWith(EndUri))
{
ResultUri = new Uri(e.Address);
this.DialogResult = DialogResult.OK;
}
}
EndUri is the final page I want to examine and ResultUri contains a string I want to extract later. Just some example code from a larger class.

CefSharp WPF web browser is not displayed Or rendered

Am new to CefSharp
I have created a class library project and referenced the CefSharp library to render the Web browser, However I am facing some issues showing the web Browser. Please find the exact code
WebBrowser_test1:
public partial class ChildWidget : Window
{
public CefSharp.Wpf.ChromiumWebBrowser webView;
public Widget()
{
InitializeComponent();
CefSharp.CefSettings settings = new CefSharp.CefSettings();
settings.PackLoadingDisabled = true;
if (CefSharp.Cef.Initialize(settings))
{
webView = new CefSharp.Wpf.ChromiumWebBrowser();
main_grid.Children.Add(webView);
webView.Address = "http://www.google.co.uk";
}
}
}
and I am referencing this library (dll) in another project
public MainWindow()
{
InitializeComponent();
Button newbutton = new Button();
newbutton.Width = 50;
main_grid.Children.Add(newbutton);
newbutton.Click += ButtonClick;
}
private void ButtonClick(object sender, RoutedEventArgs e)
{
try
{
Webbrowser_test1.ChildWidget childWidget = new Widget();
childWidget.Show();
}
catch (Exception)
{
throw;
}
}
Now on the Button click I will open the (WebBrowser_test1) child widget in which I will show the web browser .. when the window opens it is showing blank.
Please let me know if I missing anything

Subscribe to IsBrowserInitializedChanged after creating a ChromiumWebBrowser. Then once the browser is initialized you can call Load and your control will be displayed.
...
_browser = new ChromiumWebBrowser();
mainGrid.Children.Add(_browser);
_browser.IsBrowserInitializedChanged += OnIsBrowserInitializedChanged;
...
void OnIsBrowserInitializedChanged(object sender, DependencyPropertyChangedEventArgs e)
{
if (_browser.IsBrowserInitialized)
{
_browser.Load("https://www.google.com/");
}
}

I can think of the first three potential issues. But it's hard to tell what the real issue is from your code alone as it strays off a bit from the official examples
Move Cef.Initialize() to your MainWindow constructor. It should only be called once to launch the CefSharp.BrowserSubprocess.exe renderer process.
See my answer to CefSharp 3 always failing Cef.Initialize() for a few things to check regarding binaries and their placement. Really, the recommended approach is to start having the WPF example in the CefSharp.MinimalExample repo running first and then adjust to your use case from there.
I'm not sure a ChromiumWebBrowser() without explicitly setting a width and height works. A 0x0 window might not receive any rendered content. I haven't tried with recent code.

Have you tried replacing
webView.Address = "http://www.google.co.uk";
with
webView.Load("http://www.google.co.uk");

Like jornh mentions, you may have to explicitly set the height and width of the ChromiumWebBrowser. If you don't know the exact size, setting HorizontalAlignment and VerticalAlignment to Stretch (to fill the parent container) will probably also work.
Have you checked if the Cef.Initialize() actually returns true? You could be missing some files, and CefSharp doesn't always give clear error messages when this is the case.

Display WinForm when WebBrowser control finished loading

I have WinForm with WebBrowser control inside.
I am facing an annoying flicker from WebBrowser control. This is manifested that the body of WebBrowser control (or background) is shown for about 200ms before the web page is loaded and I could not get rid of it.
I want, when call myForm.Show() to see the window when WebBrowser completely finished loading and not to see this flickering.
Is there some way when calling myForm.Show() to display the WebForm page at the moment when WebBrowser control finished loading the page completely?
I know about DocumentCompleted event and read and tried some tricks mentioned here but still can not get rid of this filled blank background before web page is shown.
Any hints?

public class MyForm : Form
{
WebBrowser _Webbrowser = new WebBrowser();
TaskCompletionSource<object> _tcs = new TaskCompletionSource<object>();
public MyForm(string url)
{
_Webbrowser.ScriptErrorsSuppressed = true;
this.Controls.Add(_Webbrowser);
_Webbrowser.DocumentCompleted += (s, e) => { _tcs.TrySetResult(null); };
_Webbrowser.Navigate(url);
}
public async new void Show()
{
await _tcs.Task;
base.Show();
}
}

How should i properly invoke a WebBrowser using multiplethreads?

Problem Scope:
I'm writing an aplication to save the HTML's retrieved from the Bing and Google searches. I know there are classes to execute the Web Requests using stream such as this example, but since Google and Bing both use Javascript and Ajax to render the results into the HTML, there's no way i can simply read the stream and use get to the result i need.
The solution to this, is to use the WebBrowser class and navigate to the url i want, so that the Browser itself will handle all the Javascript and Ajax scripting executions.
MultiThreading:
In order to make it more efficient, i have the same Form aplication firing a thread for each service (one for Bing, and one for Google).
Problem:
Since i need the WebBrowser, i have instantiated one for each thread (which are 2, at this moment). According to Microsoft, there is a known bug that prevents the DocumentCompleted event from firing if the WebBrowser is not visible and is not added to a visible form aswell (for more information, follow this link).
Real Problem:
The main issue is that, the DocumentCompleted event of the browser, never fires. Never.
I have wrote a proper handler for the DocumentCompleted event that never gets the callback. For handling the wait needed for the Browser event to fire, i have implemented a AutoResetEvent with a high timeout (5 minutes), that will dispose the webbrowser thread if it does not fire the event i need after 5 minutes.
At the moment, i have the Browser created and added into a WindowsForm, both are visible, and the event is still not firing.
Some Code:
// Creating Browser Instance
browser = new WebBrowser ();
// Setting up Custom Handler to "Document Completed" Event
browser.DocumentCompleted += DocumentCompletedEvent;
// Setting Up Random Form
genericForm = new Form();
genericForm.Width = 200;
genericForm.Height = 200;
genericForm.Controls.Add (browser);
browser.Visible = true;
As for the Navigation i have the Following (method for the browser) :
public void NavigateTo (string url)
{
CompletedNavigation = false;
if (browser.ReadyState == WebBrowserReadyState.Loading) return;
genericForm.Show (); // Shows the form so that it is visible at the time the browser navigates
browser.Navigate (url);
}
And, for the call of the Navigation i have this :
// Loading URL
browser.NavigateTo(URL);
// Waiting for Our Event To Fire
if (_event.WaitOne (_timeout))
{
// Success
}
{ // Error / Timeout From the AutoResetEvent }
TL:DR:
My WebBrowser is instantiated into a another STAThread, added to a form, both are visible and shown when the Browser Navigation fires, but the DocumentCompleted event from the Browser is never fired, so the AutoResetEvent always times out and i have no response from the browser.
Thanks in Advance and sorry for the long post

Although this seems a strange way, here is my attempt.
var tasks = new Task<string>[]
{
new MyDownloader().Download("http://www.stackoverflow.com"),
new MyDownloader().Download("http://www.google.com")
};
Task.WaitAll(tasks);
Console.WriteLine(tasks[0].Result);
Console.WriteLine(tasks[1].Result);
public class MyDownloader
{
WebBrowser _wb;
TaskCompletionSource<string> _tcs;
ApplicationContext _ctx;
public Task<string> Download(string url)
{
_tcs = new TaskCompletionSource<string>();
var t = new Thread(()=>
{
_wb = new WebBrowser();
_wb.ScriptErrorsSuppressed = true;
_wb.DocumentCompleted += _wb_DocumentCompleted;
_wb.Navigate(url);
_ctx = new ApplicationContext();
Application.Run(_ctx);
});
t.SetApartmentState(ApartmentState.STA);
t.Start();
return _tcs.Task;
}
void _wb_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
//_tcs.TrySetResult(_wb.DocumentText);
_tcs.TrySetResult(_wb.DocumentTitle);
_ctx.ExitThread();
}
}