Variable Scope in ejs/express-CodePudding

So I am trying to sort out variable scope. Below is a simple snippet of code:

const params = {
      versions: versions,
      user: user,
      statsParams: statsParams,
      csrfToken: csurf.createToken(req),
    };
    res.render("server/edit", params);
    return;

Now the values that are in the params object are available in the ejs page for use. What I am seeing is that other variables that precede this code block also seem to be available in the ejs file as well not just the ones passed via the param object. Is this expected behavior? I have looked on the ejs website and it doesn't speak of variable scope.

Brad

CodePudding user response：

What you are doing with your code is rendering the page using ejs and passing the params object to the page. By passing it to the page you can render the page with access to the variables you passed in using the following tags : <%= variable =>

In terms of scope, you have now rendered the page to have access to all the variables you have passed in under the name params during the operation : res.render("server/edit", params);

If you have passed other variables through api calls to your backend you will also be able to access them in their according scope, but unless you include other variables to be passed as parameters you will not be able to access other variables from your backend.

Example :

--> userController.js

var outOfScope = True;
const params = {
  versions: versions,
  user: user,
  statsParams: statsParams,
  csrfToken: csurf.createToken(req),
};
res.render("index", params);
return;

--> index.html

...
<h1>Variable</h1>
<p><%= params.user %></p>
...

This will not work

...
<h1>Variable</h1>
<p><%= outOfScope %></p>
...

If you still have issues regarding access to variables you haven't passed it is possible you may have included them from another file by accident (ex. a header that is included).

I hope this helps, but if you are having trouble with specific variables please include them in your question as well as how you are accessing them.