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jQuery | change() with Examples

Last Updated : 16 Apr, 2020

The change() is an inbuilt method in jQuery that is used to detect the change in value of input fields. This method works only on the “<input>, <textarea> and <select&gt” elements.

Syntax :

$(selector).change(function)

Parameter: It accepts an optional parameter “function”.
Return Value: It returns the element with the modification.
jQuery code to show the working of change() method:
Code #1:
In the below code, no function is passed to the change method.

<html> 
  
<head> 
    <script src="https://ajax.googleapis.com/ajax/libs/ 
               jquery/3.3.1/jquery.min.js"></script> 
    <!--Demo of change method without passing function-->
    <script> 
        $(document).ready(function() { 
            $("button").click(function() { 
                $("input").change(); 
            }); 
        }); 
    </script> 
</head> 
  
<body> 
    <p>Click the button to see the changed value !!!</p> 
    <!--click on this button and see the change -->
    <button>Click Me!</button> 
    <p>Enter value: 
        <input value="Donald" onchange="alert(this.value)"
        type="text"></p> 
</body> 
  
</html> 

Output:
Before clicking the “Click Me” button-

After clicking the “Click Me” button-

Code #2:
In the below code, function is passed to the change method.

<html> 
  
<head> 
    <script src="https://ajax.googleapis.com/ajax/libs/  
                  jquery/3.3.1/jquery.min.js"></script> 
    <!--Here function is passed to the change method-->
    <script> 
        $(document).ready(function() { 
            $(".field").change(function() { 
                $(this).css("background-color", "#7FFF00"); 
            }); 
        }); 
    </script> 
    <style> 
        .field { 
            padding: 5px; 
        } 
    </style> 
</head> 
  
<body> 
    <!--write something and click outside -->
    Enter Value: 
    <input class="field" type="text"> 
    <p>Write something in the input field, and then 
        press enter or click outside the field.</p> 
</body> 
  
</html> 