for testing, for asp:textbox, setting text= with a variable

to test a form with tons of required fields, 45+, i was setting up the field values with text= and was trying to use variables instead of hard coded strings, but inline code, see below, is not being invoked i guess due to being enclose in the quotes.
so that after testing i could set a relatively few variables to equate to text="" and not have to reset 45 instances of text=

<asp:TextBox cssClass="textReq" columns="100" maxlength="100"  id="howHear" runat="server"
Text="<% =someVariable" %>"/>, this just resolves like any text ,  the box is rendered literally  with '<% =someVariable" %>'
so inline doesn't resolve out when in quoted property, but there is some other way to get this done?
somehow setting : System.Web.UI.Control.id(someTextBox).text??????????????????????????
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