Chrome extension - retrieving global variable from webpage

Question

I am working on an extension for Chrome. I wish parse the content of the \"original\" Gmail message (the currently viewed message).

I tried to utilize the jQuery.loa

Answer 1

Add to your content script:

function executeOnPageSpace(code){

  // create a script tag
  var script = document.createElement('script')
  script.id = 'tmpScript'
  // place the code inside the script. later replace it with execution result.
  script.textContent = 
  'document.getElementById("tmpScript").textContent = JSON.stringify(' + code + ')'
  // attach the script to page
  document.documentElement.appendChild(script)
  // collect execution results
  let result = document.getElementById("tmpScript").textContent
  // remove script from page
  script.remove()
  return JSON.parse(result)

}

Now you can do:

let window = executeOnPageSpace('window')

or even like this:

executeOnPageSpace('window.location.href = "http://stackoverflow.com"')

NOTE: I have not tested this for long-running code.