Question

Suppose I have created one jQuery function to check if elements exist or not like:

jQuery.fn.exists = function () { 
    return this.length > 0; 
}

Then I call:

if ($("#MyDiv").exists() == false)
   alert('not exist');
else
   alert('exist');

If I call jQuery function above it works. But can’t we call the jquery function like this way exists('#MyDiv') ? If I try to call this way then I am not getting result…why?

Answer 1

Try like below,

$.exists = function (selector) {
    return $(selector).length > 0;
}

and use as,

$.exists('#test') 

DEMO: http://jsfiddle.net/skram/hgaPt/1/

Please use this in a bigger picture, using it for simple thing as exist is just a overkill.