Trouble with the timing of events

Good morning ASPites,

I have a web page that contains 2 DropDownLists, a GridView and a couple of labels.  The user selects a value in ddlOne which fills the GridView. The GridView_DataBound event handler analyzes the data in the GridView and writes a value (call it Value1) to one of the labels. In the mean time, the ddlTwo_DataBound event handler does its own calculation.  It calculates a value (call it Value2) based on its selected value, ddlTwo.SelectedValue and Value1, and writes it to the second label.  My problem is that the ddlTwo_DataBound event is firing first and Value1 has not been set when the calculation for Value2 is done.

I'm sure that this is a newbie problem because I don't understand the timing of events on an ASP.NET webpage.  Any insight that you could offer would be most appreciated, thanks.

 
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