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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Build a Quiz Challenge, Part 2 Solution

Posted by Lukas Korol
Lukas Korol
2,649 Points

What's this function do?

I don't understand this function:

function print(message) {
  var div = document.getElementById('output');
  div.innerHTML = message;
}

Could someone explain? Why we cannot use simply this:

function print(message) {
  document.write(message);
}

1 Answer

miikis
miikis
44,957 Points

Hey Lucas,

function print(message) {
  var div = document.getElementById('output');
  div.innerHTML = message;
}

The above function gets the div element with the id of "output" and stores it in the variable called div. Then it makes the innerHTML of that div equal to whatever the parameter called message happens to be. (The value of message is the argument supplied to the print function ... once it's called.)

The below function...

function print(message) {
  document.write(message);
}

... works too. But it just writes plain text to the screen. That's not exactly practical.

Lukas Korol
Lukas Korol
2,649 Points

That means: I choose div to put message and by innerHTML I also get all html tags and text inside? What will be when I do without innerHTML element?

miikis
miikis
44,957 Points

"What will be when I do without innerHTML element?"

I'm not sure what you mean man... when you do what without the innerHTML method? Why don't you just try it and see what happens?

Lukas Korol
Lukas Korol
2,649 Points

Ok sorry for my stupid question. Thank you for your help!