jQuery callbacks.has() Method Last Updated : 24 Jul, 2024 Comments Improve Suggest changes Like Article Like Report The callbacks.has() method in jQuery is used to answer whether the list has any callbacks attached. If a callback is passed as an argument, then it answers whether it is on the list or not. Syntax:callbacks.has([callback])Parameters:callback: The parameter defines the callback to search for, in the list. Return Value: This method either returns true or false. Example 1: This example returns "true" because 'func' is in the list. html <!DOCTYPE HTML> <html> <head> <script src= "https://code.jquery.com/jquery-3.5.0.js"> </script> </head> <body style="text-align:center;"> <h1 style="color:green;"> GeeksForGeeks </h1> <p> jQuery | callbacks.has() method </p> <button onclick="Geeks();"> Click Here </button> <p id="GFG"></p> <script> let el_down = document.getElementById("GFG"); let res = ""; let callbacks = jQuery.Callbacks(); function Geeks() { let func = function (val) { res = res + "value passed is - " + val; }; callbacks.add(func); // function added to list callbacks.fire("gfg_1"); el_down.innerHTML = callbacks.has(); } </script> </body> </html> Output: Example 2: This example returns "false" because 'func2' is not in the list. html <!DOCTYPE HTML> <html> <head> <script src= "https://code.jquery.com/jquery-3.5.0.js"> </script> </head> <body style="text-align:center;"> <h1 style="color:green;"> GeeksForGeeks </h1> <p> jQuery | callbacks.has() method </p> <button onclick="Geeks();"> Click Here </button> <p id="GFG_DOWN"></p> <script> let el_down = document.getElementById("GFG_DOWN"); let res = ""; let callbacks = jQuery.Callbacks(); function Geeks() { let func1 = function (val) { res = res + "value passed is - " + val; }; let func2 = function (val) { res = res + "value passed is - " + val; }; // Function added to list callbacks.add(func1); callbacks.fire("gfg_1"); el_down.innerHTML = callbacks.has(func2); } </script> </body> </html> Output: Comment More infoAdvertise with us Next Article jQuery callbacks.has() Method P PranchalKatiyar Follow Improve Article Tags : JavaScript Web Technologies JQuery jQuery-Methods Similar Reads jQuery callbacks.fire() Method The jQuery callbacks.fire() method is used to call all the callbacks with the given arguments in the list. This method returns the callbacks object onto which it is attached (this). Syntax:callbacks.fire( arguments )Parameters:arguments: This parameter defines the argument or list of arguments to pa 2 min read jQuery callbacks.fired() Method The jQuery callbacks.fired() method is used to check if the callbacks have already been called at least once. This method returns the Boolean value.Syntax:callbacks.fired()Parameters: This method does not accept any arguments.Return Value: This method returns a Boolean value.Example 1: This example 2 min read jQuery callbacks.empty() Method The callbacks.empty() method in jQuery is used to remove all the callbacks from a list. It returns the Callbacks object onto which it is attached.Syntax:callbacks.empty()Parameters: It does not accept any parameter.Return Value: This method returns the Callbacks object onto which it is attached.Belo 3 min read JQuery callbacks.disable() method This callbacks.disable() method in jQuery is used to disable a callback list from doing any other operation further. This method returns the Callbacks object onto which it is attached (this).Syntax: callbacks.disable()There are two examples discussed below: Example: This example disables the callbac 2 min read jQuery callbacks.fireWith() Method The callbacks.fireWith() method in jQuery is used to call all the callbacks which are currently in the list with the given context and parameters.Syntax:callbacks.fireWith([context][, params])Parameters:context: This parameter defines the reference to the context in which the callbacks in the list s 2 min read Like