jQuery was providing unique number for dom elements ?

I was remembering that there was a jquery method which provide unique number for dom elements. It just may for only animated dom objects. Now I couldn't find that method. What is开发者_如何转开发 that method ? Is there any another way to provide unique number for elements ?

I think you may be thinking about the concept of jQuery.expando. There is an attribute called jQuery.expando that exists on every page that has jQuery running. It is defined like this:

expando: "jQuery" + ( jQuery.fn.jquery + Math.random() ).replace( /\D/g, "" ),

So for me, on the current page, it is jQuery15209244967177268291. Any element that has any data stored on it (including event handlers, which are stored as data) has a property with that name. This contains a unique number, which is the key for that element in the global data cache.

For instance, with the global StackExchange inbox on the top left of the screen:

$('.genu')[0].jQuery15209244967177268291 === 29

You can mimic this with $('.genu')[0][jQuery.expando]; I'm not sure whether you'll get the same number. (Edit: it's not even the same number for me every time.)

Note, however, that not every element has a unique number, only those with data attached to them. This may or may not fit your purposes...

The only thing that looks remotely like what you might be after is the jQuery.unique(), but even that doesn't do what you're suggesting. I would encourage you to update your question to state the purpose for this, as there may be a better way to solve the problem that is prompting you to get unique numbers for each element.