Check if object is an event in JS
86651
How to determine if Javascript object is an event?
30987
How to tell if a JavaScript function is defined
44858
JavaScript isset() equivalent
14704
How to detect if a variable is an array
34109
Detect changes in the DOM
63621
AJAX: Check if a string is JSON?
131495
What does ‘::’ (double colon) do in javascript for events?
103062
How do I check whether a checkbox is checked in jQuery?
147070
Monitor All JavaScript Object Properties (magic getters and setters)
74136
cloning javascript event object
110541
How to check whether dynamically attached event listener exists or not?
126638
How can I determine if a jQuery object is deferred?
134205
pure javascript to check if something has hover (without setting on mouseover/out)
37773
How do I detect whether a Python variable is a function?
118611
Determine list of event handlers bound to event
154253
DOM event precedence
37735
How can I check for "undefined" in JavaScript?