Can C# Program Learn When Some Processing Completes on an Angular Web Page?

[afbarksd]

We are new to CefSharp and are trying to decide whether to use it. A capability that we would like to have is this:

 [1] A C# program displays a web page created with Angular, presumably through passing the URL to ChromiumWebBrowser.

 [2] On the web page, the user keys in text to fields and then clicks a button, which causes processing based on the input text.

 [3] When the processing completes, we would like to have a way -- perhaps through an event handler -- whereby the C# program can learn that the processing is complete.  It would be good but not required for the C# program to get a string with the results of the processing.

Is the preceding possible through CefSharp?

[ukandrewc]

Yes that is possible, you can add an event listener to the button, then call a method in C#.
Have a read here: https://github.com/cefsharp/CefSharp/wiki/General-Usage

[afbarksd]

I could add an event listener to the button similarly to how an event listener is added to document in https://github.com/cefsharp/CefSharp/wiki/General-Usage. However, the function passed to addEventListener is a script function, not a C# function. I do not see how the listener could call a method in the C# program or send an event to the C# program.

[ukandrewc]

Two methods: One is to register your own object (class) and call a method in that, but simplest is:

CefSharp.PostMessage("Hello")

Which is received in JavascriptMessageReceived.

Here's a sample: https://github.com/cefsharp/CefSharp/wiki/Frequently-asked-questions

[afbarksd]

Thanks! That worked. When I scanned the FAQ upon my first looking at CEFSharp, https://github.com/cefsharp/CefSharp/wiki/Frequently-asked-questions#JSEvent didn't register in my memory.