How can I tell of a HTML attribute exists or not, using Javascript

Question

I'm trying to convert to HTML5, but to preserve the site experience for those that don't have all the HTML5 features, I would use a workaround. For example, how can I check if the HTML5 attribute contentEditable exists, so that if it doesn't, I can just create a textarea instead.

Thaks!

Answer 1

这可以提供帮助： http ： //diveintohtml5.ep.io/detect.html

Answer 2

The following snippet checks if the 'contentEditable' property exists.

if('contentEditable' in element){
   // contentEditable is available
}
else{
   // create textarea
}

Answer 3

According to HTML5 Peeks, Pokes and Pointers :

"isContentEditable" in document.createElement("a")

You can replace the document.createElement("a") with any element, really, so if you already have an element you're working with, use that.