How I can get all requests of network by using Cefsharp

[fantast]

For example:
Now, requests count = 100
A friend send me a chat message and I see messager have symbol 1 highlight (new message from one friend)
Then, requests count = 101

I want listening when Viewer ( ChromiumWebBrowser.Load(url) ) get new request (because requests count is high changing), i will do my task MyFunction()
How I can catch this event or how i can catch this sign?

My idea like this:
When Textbox RequestCounting receiverd new request
I will using TextChanged event to catched this event.
After, using MyfFunction() into TextChanged event

Please help me, i find a little information of Cef API maybe useful but no have any example explain it: IRequestHandler.OnResourceResponse, OnBeforeResourceLoad