ExpressJS Pass variables to JavaScript

Question

I am completely lost on this; I am using NodeJS to fetch a JSON and I need to pass the variable to my page and have JavaScript use the data.

app.get('/test', function(req, res) {
    res.render('testPage', {
        myVar: 'My Data'
    });

That is my Express code (very simple for testing purposes); now using JADE I want to gather this data which I know to render on the page is simply

p= myVar

But I need to be able to gather this data in JavaScript (if possible within a .js file) but for now just to display the variable in an Alert box I have tried

alert(#{myVar})

And many others if anyone can help be much appreciated

Answer 1

Try the following:

alert('!{myVar}')

It's a good idea to JSON encode the data if is more than just a string.

alert('!{JSON.stringify(myVar)}')

Answer 2

As Timothy said:

<script type="text/javascript"> var myVar = #{JSON.stringify(myVar)}; </script>

This can also be done as follows in if you don't like to write HTML in Jade/Pug templates:

script
  var myVar = !{JSON.stringify(myVar)};
  var myVar2 = !{JSON.stringify(myVar2)};

Update: For Express 4 and Pug use script. instead of script so that it will be rendered as javascript instead of html.