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JavaScript

Posted by Liam Hayes
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Liam Hayes
Full Stack JavaScript Techdegree Student 13,116 Points

I don't know how to get Professor McFarland's print function to work

How's it going guys? =)

This is a function that Professor McFarland talks about in one of the videos: 

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

He says that it is superior to writing document.write("hello world");. I want to use it but I can't get it to work. For example, if I call it like this print("hello world");. the following error appears:

- Error in this line:  div.innerHTML = message;
- Uncaught TypeError: Cannot set property 'innerHTML' of null

Does anybody know what I can do to make this function work so I can use it instead of using document.write()?

Thank you!!

1 Answer

Steven Parker
Steven Parker
243,228 Points
Steven Parker
Steven Parker
243,228 Points

Check your HTML code. That's the error I would expect to see if there is not any element which has the "id" attribute set to "output".

Your HTML should include something like this:

<div id="output"></div>
Liam Hayes
.a{fill-rule:evenodd;}techdegree
Liam Hayes
Full Stack JavaScript Techdegree Student 13,116 Points

I will try that. Thank you Steven :)