Which events are attached to an element?

How can I receive all events attached to an element with do开发者_开发技巧jo?

dojo.query('#mydiv') // which events does #mydiv has?

To get all events on a DOM element:

// Get my div
myDiv = dojo.byId("myDiv");
// Obtain all event-related attributes
var events = dojo.filter(
    myDiv.attributes, 
    function(item) { 
        return item.name.substr(0, 2) == 'on';
    }
);
// Execute first found event, just for fun
eval(events[0].value);

If you get myDiv using dojo.query, remember that dojo.query returns an array, so your element would be in myDiv[0].

This solution does not work with events attached with dojo.connect. There probably is a way to extract this info from Dojo inner workings, but you would have to delve into the source code to understand how.

Another option is that you explicitly manage all dojo.connect events with a global registry. You could use dojox.collections to make this easier. For example, creating a global registry whose keys will be the dom nodes, and values will be the handles returned by dojo.connect (these handles contain the dom node, the type of event and the function to execute):

// On startup
dojo.require(dojox.collections.Dictionary);
eventRegistry = new dojox.collections.Dictionary();
...
// Registering an event for dom node with id=myDiv
var handle1 = dojo.connect(dojo.byId("myDiv"), "onclick", null, "clickHandler");
// Check if event container (e.g. an array) for this dom node is already created
var domNode = handle1[0];
if (!eventRegistry.containsKey(domNode))
    eventRegistry.add(domNode, new Array());
eventRegistry.item(domNode).push(handle1);
...
// Add another event later to myDiv, assume container (array) is already created
var handle2 = dojo.connect(dojo.byId("myDiv"), "onmouseover", null, "mouseHandler");
eventRegistry.item(domNode).push(handle2);
...
// Later get all events attached to myDiv, and print event names
allEvents = eventRegistry.item(domNode);
dojo.forEach(
    allEvents, 
    function(item) {
        console.log(item[1]); 
       // Item is the handler returned by dojo.connect, item[1] is the name of the event!
    }
);

You can hide the annoying check to see if event container is already created by creating a subclass of dojox.collections.Dictionary with this check already incorporated. Create a js file with this path fakenmc/EventRegistry.js, and put it beside dojo, dojox, etc:

dojo.provide('fakenmc.EventRegistry');
dojo.require('dojox.collections.Dictionary');
dojo.declare('fakenmc.EventRegistry', dojox.collections.Dictionary, {
    addEventToNode : function(djConnHandle) {
        domNode = djConnHandle[0];
        if (!this.containsKey(domNode))
            this.add(domNode, new Array());
        this.item(domNode).push(djConnHandle);
    }
});

Using the above class you would have to dojo.require('fakenmc.EventRegistry') instead of 'dojox.collections.Dictionary', and would simply directly add the dojo connect handle without other checks:

dojo.provide('fakenmc.EventRegistry');
eventRegistry = new fakenmc.EventRegistry();
var handle = dojo.connect(dojo.byId("myDiv"), "onclick", null, "clickHandler");
eventRegistry.addEventToNode(handle);
...
// Get all events attached to node
var allEvents = eventRegistry.item(dojo.byId("myDiv"));
...

This code is not tested, but I think you get the idea.

If its only for debugging purpose. You can try dijit.byId("myId").onClick.toString(); in your firebug console and you can see the entire onclick code this works even if the function is anonymous you can view the content of anonymous content.