How can I show some type of message in my ASPX web page ( *I'm using WebForms, not MVC* ), which represents as a "wait process" while some method of my project is executing.

I'm not asking about how to make some HTML/CSS/DOM stuff, I'm asking more about asynchronous check.

**For e.g.:** some data from web could be delivered to client not quickly and when it does occur - it looks very ugly for the user. It's just idling and looks like a page with bug, where there is no well highlighted status ( *many users don't watch in browsers the page loading states, they want to look it in web applications exactly, like in desktop applications* ).

I want to show a message like ***"waiting for the operation end"***
and I don't know how to make an asynchronous check in my ASPX page for getting the current state when some methods execute ( *are they finished or not etc...* ).

What I really want looks like in pseudo-code:

```
while (methodExecuting) show(waitMessage);

```

How could it be done in WebForms of ASP.NET project?