how to create own function in JQuery?

Question

how to create own function and call it another function? like-

$('.mycls li').hover(function() {    
var divid = $(this).find('li').attr('some_attr');
call myfunc(divid);
});

function myfunc(divid)
{
$(divid).show();
//I want to hide rest all divs 
$('div#info1').hide();
$('div#info2').hide();
$('div#info3').hide();
}

I have 2 questions one is how to implement this logic in jquery second is which attribute can be used to reference the specific li to specific div

my divs are as-

<div id="info1">
//some information
</div>
<div id="info2">
</div>
....

Answer 1

Your functions should be able to operate on the wrapped set like other methods/functions of jquery. Consider a plugin, it is easy:

jQuery Plugin Tutorial

Or see:

Defining your own functions in jQuery

Answer 2

I wrote this:

jQuery.fn.doSomeStuff = function(options, callback) {
    var $elem = $(this[0]);
    var args = options || {};
    
    // doSomeStuff
    alert("DOM element: "+$elem.html());
    alert("this ia a parameter:"+ args.aParameter);
    
    if (typeof callback == 'function') { // make sure the callback is a function
        callback.call(this); // brings the scope to the callback
    }
    return $elem; //ensures jquery chainability
};

1. define your own function
2. specify parameters and callback
3. ensure jquery chainability

You can try it here