Question

I have some jQuery code:

$(function(){ 
function someFunc(){
    /*do something*/
};
.............   
});

And now I want call someFunc from JavaScript like below:

function test(){    
$.fn.someFunc();
}

But it doesn’t work! I’ve seen an article how to call function in jquery from javascript. Is it possible?

Answer 1

Just defining a function within the closure (function) you pass into $() doesn’t do anything to put it on the jQuery fn object. To do that, you have to do it explicitly:

$.fn.someFunc = someFunc;

Typically, you wouldn’t do this within a callback on $(), you’d do it earlier. Plug-ins do this to add functionality, which should already be present prior to DOM ready.

By way of example, here’s a silly little plug-in that turns text green:

(function($) {
  $.fn.green = green;
  function green() {
    return this.css("color", "green");
  }
})(jQuery);

…which you might use from DOM ready:

jQuery(function($) {

  $(".foo").green();

});

Live example | Live source

Note that the call to it is from a jQuery instance, not directly from $.fn.