Question

I’ve been making a concerted effort to improve my javascript skills lately by reading as much javascript code as I can. In doing this I’ve sometimes seen the javascript: prefix appended to the front of event handler attributes in HTML element tags. What’s the purpose of this prefix? Basically, is there any appreciable difference between:

onchange='javascript: myFunction(this)' 

and

onchange='myFunction(this)' 

?

Answer 1

Probably nothing in your example. My understanding is that javascript: is for anchor tags (in place of an actual href). You’d use it so that your script can execute when the user clicks the link, but without initiating a navigation back to the page (which a blank href coupled with an onclick will do).

For example:

<a href='javascript:someFunction();'>Blah</a> 

Rather than:

<a href='' onclick='someFunction();'>Blah</a>