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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Adding Data to Arrays

Posted by john larson
john larson
16,594 Points

have I got this print function parameter passing thing right?

/*.........print function.......*/
function print(message) { /* to be printed passed to print(message) */
  return document.getElementById("print").innerHTML = message;
  /* innerHTML = message is passed to (message)
  and then printed to the page */
}

2 Answers

jcorum
jcorum
71,830 Points

You use return when you want something back from your function, e.g., a value, . Take this example:

function square(x) {
   return x * x;
}

You give the function a value, x, and you want it to return the square of that value.

But in your case, you didn't need any value back. You just wanted the function to print a message to the page.

john larson
john larson
16,594 Points

Thanks j, I think I get it.

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

If you just want to display message on the page, then there's no need for the return. Just do it like this:

function print(message) { 
  document.getElementById("print").innerHTML = message;
}

This code assumes there is an element on the page with an id of print.

john larson
john larson
16,594 Points

there is an id of print on the page for my innerHTML, and I thought Dave was using a return but I looked again and he wasn't. I'm still foggy on when return is necessary. Thanks for your feedback.