jQuery callbacks.lock() Method

Last Updated : 23 Jul, 2024

The callbacks.lock() method in jQuery is used to lock a callback list in the state.

Syntax:

callbacks.lock()

Return Value:

This method returns the callback object to which it is attached.

Example 1:

This example first adds and fires the function, then locks the callbacks list, and then again adds and fires the function.

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.lock() 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 func = function (val) {  res = res +   "value passed is - " + val;  };  // Function added to list  callbacks.add(func);  callbacks.fire("gfg_1");  // Locking the callback list  callbacks.lock();   // Function again added to list  callbacks.add(func);   callbacks.fire("gfg_2");  el_down.innerHTML = res;  }   </script> </body> </html>

Output:

Example 2:This example provides a button to lock the list and then add and fire the function to check whether the method is working or not.

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.lock() method </p> <button onclick="Geeks();"> click here </button> <button onclick="lock();"> lock here </button> <p id="GFG_DOWN"></p> <script>  var el_down = document  .getElementById("GFG_DOWN");  var res = "";  var callbacks = jQuery.Callbacks();  function lock() {  callbacks.lock();  }  function Geeks() {  // Function to be added to the list  var fun = function (val) {  res = res + "This is function and "  + "value passed is " + val + "<br>";  };  callbacks.add(fun); // Adding  callbacks.fire("GFG_1");  el_down.innerHTML = res;  }   </script> </body> </html>