TextBox TextChanged event doesn't fire in the second try

Hi,
I'm writing an web application for a terminal (Window CE device that function as a barcode also) in c#.
I have a textbox for getting the Barcode (not by typing, by firing the "barcode laser gun").. and I'm using the OnTextChanged event:
<asp:TextBox ID="txtBarcode" CssClass ="TextBox" AutoPostBack ="true" OnTextChanged ="SetDate" runat="server"></asp:TextBox>
The first time it firing, but if I snipe the same barcode again (no change was done on the textbox) obviously it will not fire again.
How can I make it work also in the second try?! is there a KeyPress event or Enter event for textbox in web site applications?



Thanks in advance.

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