How can I retrieve a list of event listeners bound to an element using jQuery?

Retrieving Event Listeners Assigned to an Element Using jQuery

In JavaScript, attaching event handlers to elements is a common practice for enhancing user interaction. jQuery provides robust event handling capabilities, making it easy to assign and manage event listeners on elements. This raises a question: can we retrieve a list of events bound to a specific element using jQuery?

Problem:

Scenario: We have an element with an ID "elm" and we have attached two event handlers to this link – one for click event and another for mouseover event.

<a href='#'>

$(function()
{
  $('#elm').click(_f);
  $('#elm').mouseover(_m);
});

function _f(){alert('clicked');}
function _m(){alert('mouse over');}

Is there a way to obtain a list of all events associated with the element with ID "elm"?

Answer:

In recent versions of jQuery, the $._data method can be used to retrieve information about an element, including any events bound to it. It's worth noting that $._data is an internal-use only method.

// Bind up a couple of event handlers
$("#foo").on({
    click: function(){ alert("Hello") },
    mouseout: function(){ alert("World") }
});

// Lookup events for this particular Element
$._data( $("#foo")[0], "events" );

$._data will return an object containing the events attached to the specified element.

{ 
    click: [
        {
            handler: function(){ alert("Hello") }  // The defined click handler
        } 
    ],
    mouseout: [
        {
            handler: function(){ alert("World") }  // The defined mouseout handler
        }
    ] 
}

In Chrome, you can right-click the handler function and select "view function definition" to trace its origin in your code.

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