Tutorialspoint.dev

jQuery | undelegate() with Examples

The undelegate() method is an inbuilt method in jQuery which is used to remove the specified event handler from the selected element.

Syntax:

$(selector).undelegate(selector, event, function)

Parameters: This method accepts three parameters as mentioned above and described below:



  • selector: It is an optional parameter which is used to specify the selector from which event will remove.
  • event: It is an optional parameter which is used to specify the name of the event type on the selector.
  • function: It is an optional parameter which is used to specify the name of the handler function to remove.

Return Value: This method returns the selected element with specified changes made by undelegate() method.

Below examples illustrate the undelegate() method in jQuery:

Example 1: This example does not contain any parameters.

<!DOCTYPE html>
<html>
    <head>
        <title>The undelegate Method</title>
        <script src=
        </script>
          
        <!-- jQuery code to show the working of this method -->
        <script>
            $(document).ready(function() {
                $("body").delegate("p", "click", function() {
                    $(this).css("font-size", "25px");
                });
                $("button").click(function() {
                    $("body").undelegate();
                });
            });
        </script>
        <style>
            div {
                width: 300px;
                height: 100px;
                background-color: lightgreen;
                padding: 20px;
                font-weight: bold;
                font-size: 20px;
                border: 2px solid green;
            }
            button {
                margin-top: 10px;
            }
        </style>
    </head>
    <body>
        <div>
            <!-- click on this p element -->
            <p>Welcome to GeeksforGeeks!.</p>
        </div>
        <!-- click on this button to remove the 
        event handler -->
        <button>Remove...!</button>
    </body>
</html>                                            

/div>

Output:
Before click anywhere:

After click on the paragraph:

Note: First click on the button and then click on the paragraph, then no changes occur.

Example 2: This example contains all parameters.

<!DOCTYPE html>
<html>
    <head>
        <title>The undelegate Method</title>
        <script src=
        </script>
          
        <!-- jQuery code to show the working of this method -->
        <script>
            $(document).ready(function() {
                $("body").delegate("div", "click", function() {
                    $(this).animate({
                        height: "+=100px"
                    });
                    $(this).animate({
                        width: "+=100px"
                    });
                });
                $("button").click(function() {
                    $("body").undelegate("div", "click");
                });
            });
        </script>
        <style>
            div {
                width: 30px;
                height: 30px;
                background-color: green;
            }
            button {
                margin-top: 10px;
            }
        </style>
    </head>
    <body>
        <div></div>
        <!-- click on this button -->
        <button>Click here..!</button>
    </body>
</html>

Output:
Before clicking anywhere:

After clicking on the div element get resized.

Note: If click on the button and then click on the div element then no change in the size will take place.



This article is attributed to GeeksforGeeks.org

You Might Also Like

leave a comment

code

0 Comments

load comments

Subscribe to Our Newsletter