How to call a function that is using window.onload from another function

Question

I'm trying to use questionFunction() again once the user clicks a button which calls myFunction but I'm getting an error 'questionFunction is not defined'

window.onload = function questionFunction() {
  var questionText = document.getElementById("question").innerHTML = randomNumber1 + " " + operationArray[randomOperation1] + " " + randomNumber2 + " " + operationArray[randomOperation2] + " " + randomNumber3;
}

function myFunction() {
return questionFunction();
}

I wan't the text to be changed on load and also again once the user clicks to call myFunction()

Answer 1

function questionFunction() {
  var questionText = document.getElementById("question").innerHTML = randomNumber1 + " " + operationArray[randomOperation1] + " " + randomNumber2 + " " + operationArray[randomOperation2] + " " + randomNumber3;
}

window.onload = questionFunction;

function myFunction() {
  return questionFunction();
}

This will work. You're getting error because of wrong function scope.

You can read about it here:

https://javascriptweblog.wordpress.com/2010/07/06/function-declarations-vs-function-expressions/