Question

I would like to use createElement(“img’) to create .jpeg extension instead of .png

According to Flanagan’s book JavaScript: The Definitive Guide: Activate Your Web Pages By David Flanagan,

For jpeg image type, the second argument should be a number between 0
and 1 specifying the image quality level.

I am not sure what the syntax for the code would be.

Is it something like this?

createElement("img",1)

Answer 1

The book is talking about html5’s canvas tag and specifically its .toDataURL method.

I think you want to do something like:

var img = document.createElement('img');
img.src = 'myImageSource.jpg';

In this case, it’s up to the web server to deliver the image and its type information to the web browser.