problems with parameters in class

I have two simple user control. in first i have a textbox (enter name of car) and button (confirm), and in second i have dropdownlist and i've enterd manually data in it.
I also have one class with one property of car and i want to make in my first control enter name of car, choose name of driver in dropdown list and print it on label. I don't wok anithing in my default.aspx only in ascx files.


My problem is next, when i call first user control my constructor in class delete my car properties and than it is empty, without values. How to hold that value.
my goals is simple, use update panell trigger in two user control, and if someone have some usefull tutorials it woud be wonderfull.


Thanks.

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