Knowledge Check - JavaScript in the browser

In the following code, the type attribute can be omitted.

 <script type="text/javascript">
     //Comment
 </script>

• true

• false

What does the document variable return in JavaScript?

 console.log(document);

• The entire body tag of the webpage in the browser's memory, as a JavaScript object.

• The entire webpage in the browser's memory, as a JavaScript object.

• The HTML code of the downloaded webpage, as a JavaScript string.

What does the following function return?

 getElementById('main-heading')

• It doesn't return anything.

• All elements that have the class attribute with a value main-heading

• The first element that has the id attribute with a value main-heading

• The last element that has the id attribute with a value main-heading

After the following code is run, what will happen when the user clicks on a p element in the browser?

 document.querySelector('h1').addEventListener('click', function() { 
     console.log('clicked');
 });

• 'clicked' is printed to the console log.

• Nothing.

What will be printed when the following code runs?

 var result = {
     value: 7
 };
 console.log(JSON.stringify(result));

• {}

• {value: 7}

• {"value": 7}