Node.js pass a value to a partial view - node.js

Question

I have a route that looks like this:
app.get('/Search', function (req, res) {
var searchString = req.query.SearchString;
var request = require('./cstapi')(searchString, onBody);
function onBody(body) {
res.render('index', { output: body });
}
});
and an index.ejs that looks like this:
<div id="searchDiv">
<% include ../partials/search %>
<br>
<% include ../partials/results %>
</div>
search looks like this:
<form action="./search" method="GET">
<input type="text" name="SearchString" class="form-control" >
<input type="submit" value="Search" class="form-control">
</form>
and results looks like this:
<p>Search returned the following: <%= output %></p>
I'm trying to get the search results to display in a partial view after the user submits the form. With the above I get output is not defined when attempting to render index and the subsequent partial views.

Answer 1

I found a work around although I'm not 100% sure this is the best way of doing it:
By adding 'null check' to output in index I can avoid the output not defined error when accessing the results partial without search results.
So index now becomes:
<div id="searchDiv">
<% include ../partials/search %>
<br>
<%if (typeof output !== 'undefined') { %>
%> <% include ../partials/results %>
<% } %>
</div>
Hopefully someone can provide a better way?