Will RenderMode.InteractiveServer ALWAYS call OnInitializedAsync() twice?

[DavidThielen]

Hi all;

First, to make sure I understand InteractiveServer correctly, it is calling OnInitializedAsync() twice. First to get the HTML skeleton (my word) of the page up ASAP. So the entire page, but text boxes, grids and lists are empty; combo boxes, etc. don't have their allowed choices, etc. So the full page, but no data.

And the interactive controls are not (yet) wired up between the client and server. So it's a static page as well as having no data.

Then OnInitializedAsync() is called again and this time we want the fully populated page, with the interactive controls wired up between client and server.

1. Is this correct?

If so, then instead of reading in the data on the first call and caching it to supply again on the second call, wouldn't it be better to not hit the database at all on the first call? Because the goal on the first call is speed?

2. Is there any downside to not populating the controls on the first call to OnInitializedAsync()?
3. Will it always call OnInitializedAsync() exactly twice?

And then, assuming the above is correct, there's the critical question:

4. How do I know if I'm being called the first time or the second time?

And then finally, out of curiosity:

5. Why didn't they create a new event. So we would get called by OnInitializedAsync() and then by OnPopulatePageAsync()?

thanks - dave