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JavaScript

Posted by eslam said
eslam said
Courses Plus Student 6,734 Points

Brackets and javascript

I`m using brackets and i linked my script.js to html like that :

 <script src="script.js"></script>

and here is my html

<h1 id="main-heading">No subject is terrible if the story is true.</h1>

and here is my js

onclick='document.getElementById("main-heading").style.display="none"';

dont worry about the code i am just practicing nothing more but its not working and i`m getting weird errors in brackets like the following :

  • 'onclick' was used before it was defined.

3 Answers

Steven Parker
Steven Parker
243,318 Points
Steven Parker
Steven Parker
243,318 Points

If that's the only line of JavaScript the error makes perfect sense. Were you trying to access the "onclick" property of the h1 element? As shown, it should be part of the h1 header, not separate code. A code version might look like this:

document.getElementById("main-heading").onclick = function() {
    this.style.display = "none";
};

And here it is inserted into the HTML instead:

<h1 id="main-heading" onclick='document.getElementById("main-heading").style.display="none"'>
    No subject is terrible if the story is true.
</h1>
eslam said
PLUS
eslam said
Courses Plus Student 6,734 Points
eslam said
eslam said
Courses Plus Student 6,734 Points

Thanks steven for your answer and yes i was trying to access the h1 element, can you give me further explanation of what`s happening ?

Steven Parker
Steven Parker
243,318 Points
Steven Parker
Steven Parker
243,318 Points

From the code standpoint "onclick" hasn't been defined yet, or associated with a specific element. But it could be directly assigned in the element tag.

Dave StSomeWhere
Dave StSomeWhere
19,870 Points

As Steven has said, "onclick()" needs to be associated with an element and doesn't stand alone as per your original statement. "onclick()" is a method associated with an element. The key thing to recognize from Steven's examples is that in the first one you see ".onclick()" because it is a valid method of document.getElementByID() and in the second one, it is one of the valid <h1> element properties.

So... brackets sees you using onclick and thinks it is a variable name (as opposed to the desired method onclick() and doesn't see a declaration for it.

Make sense?

eslam said
PLUS
eslam said
Courses Plus Student 6,734 Points
eslam said
eslam said
Courses Plus Student 6,734 Points

Thank you for your answers