ASP.NET User Control, DataGrid, CRUD Issues

Question

Hi all

I'm working with a user control (one panel with a Button and a DropDownList) in my ASP.NET application, that is triggered by a GridView. An ID of one record is passed as a CommandArgument each time a button in the GridView is clicked, and my control is displayed via the RowCommand event handler:

myControl.CurrentID = Guid.NewGuid(); // instead a real GUID is passed

My control has a DropDownList (dynamically populated) and a save button. I do need to populate my DropDownList, select the current value. When the used clicks save, I need to save the new value.

My issues with this:

• In the control's Page_Load the CurrentID is still empty, as it's populated later on in the lifecycle. What's the most elegant way to handle this in the correct order. Using PreRender instead...?
• How can I distinguish Page_Load invoked by my save button or by the outer page's Grid? IsPostBack does not help, since the RowCommand event is a PostBack too, obviously.
• In general: What are the best practices here? I'm pretty confused at the moment, not sure whether there's a simple and clear solution that I just don't see :)

Thanks for any idea!

Cheers Matthias