AutoCompleteExtender and Collection of objects

hi
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vs2008
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The code below is some code which is being executed when user types in a
textbox..
This method returns an array of strings which is shown as a dropdown list
added to the listbox...
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As you see from the code below first a collection of Cars is added to the
CarCollection variable, and then a loop goes through all objects in that
collection and subtract the "make" of the car and add it to a string
array...
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that's fine but each Car object contain's an Id which I want to get. Lets
say this AutoCompleteExtender shows a list of 5 strings. The user select one
of those string items. But the info in the textbox isn't saved to the
database, the "Id" is saved to the database.
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any ideas how to get that "Id". I could for example when saving it perform a
select in the stored procedure which gets the "id", but I thought maybe
there are a better solution to this. I mean the "Id" is retrieved already so
hope I can avoid making another retrieve. In addition the Car object has
more info which I would like to be displayed when the user select a specific
car
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any suggestions?
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[WebMethod]
public string[] GetCompletionList(string prefixText, int count)
{
List<CarCarCollection = Car.GetCars(prefixText, count);
List<stringCars = null;
foreach (Car car in CarCollection)
{
Cars.Add(car.make);
}
return Cars.ToArray();
}
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