Write VB code in .JS file

Is it possible to write a vb code inside a file that looks like .js?

For example: arquivo teste.js

var testeEvento = function () {
    <%=MsgBox("teste")%>;
    };

I tried this way it did not work, it returns me this:

Uncaught SyntaxError: Unexpected token <

And when running:

Uncaught ReferenceError: testeEvento is not defined
    at <anonymous>:1:1