Why canvas is not a self closing HTML5 tag

While debugging a page produced by our PDF to HTML5 Converter, I noticed that Firefox was showing some of the tags in the HTML source in red.

Specifically, there was a closing div tag.

 

The solution I thought was quite obvious – there must be no opening div tag for it to close.
But scrolling up, indeed there was a div tag for it to close.

The problem itself was actually in the line above – the canvas tag.

The line used was <canvas id=”pdf15″ width=”1053″ height=”813″ >. Although our canvas tag has nothing inside it because of the way that the canvas works, that doesn’t mean that we are allowed to self close it like we would an </canvas>.

The reason that canvas tag requires a separate closing tag is because it’s actually possible to put content inside that will display instead of the canvas if the user’s browser does not support HTML5.

 

Problem solved!

This post is part of our “HTML5 Article index” in these articles, we aim to help you understand the world of HTML5.

Related Posts:

The following two tabs change content below.
Leon is a developer at IDRsolutions and product manager for JPDF2HTML5. He is responsible for managing the JPDF2HTML5 product strategy and roadmap, and also spends a lot of his time writing code to build new features, improve functionality, fix bugs, and improve the testing for JPDF2HTML5.
Leon Atherton

About Leon Atherton

Leon is a developer at IDRsolutions and product manager for JPDF2HTML5. He is responsible for managing the JPDF2HTML5 product strategy and roadmap, and also spends a lot of his time writing code to build new features, improve functionality, fix bugs, and improve the testing for JPDF2HTML5.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes:

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>