embed MVC script block in jQuery

I am trying to mix MVC2 <%: %> script block in jQuery script. It takes the user entry, changes the form action attribute with the Url.RouteUrl(), and post the form when the text box loses focus. Here is a section of a appScript.js file

$("input#txtSSN").blur(function () {
    if ($(this).val() != undefined && jQuery.trim($(this).val()).length != 0) {
        alert('txtSSN.blur() = ' + $(this).val());
        var formAction = '<%:Url.RouteUrl(new { controller = "controller1", action = "SSN", ID = escape(jQuery.trim($(this).val())) }) %&开发者_开发问答gt;';
        $(this).parents('form:first').form.attr('action', formAction);
        $(this).parents('form:first').submit();
    } //if
}); //blur

This .js is referenced the Site.master "script src=" block. Everything works except it doesn't post the form with the updated href. Thanks for your help.

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You can use the server code blocks only in the aspx files, not in external .js files