Submit Form Without Submit Button?

Is it possible to POST a form without relying on the pressing of a Submit button?
I am trying to post a values to a PHP form that will use its $_POST method to get that values.  I realize that I can do this:
<form runat="server" action="admin/index.php?a=do_login" method="post"> User Name: <input type="text" name="user" value="cbouknight" /> Phone: <input type="text" name="state" value="MD" /> <asp:Button id="Button1" Text="Submit" runat="server" /> </form> This works, but I would rather that users are sent to the page via a menuitem instead of pressing a button on a form. Is there a way to do this, and is there also a way to use public properties instead of input fields? ...