JavaScript onKeyPress onKeyUp and onKeyDown Events

Whenever a key is pressed or released, there are certain events that are triggered. Each of these events has a different meaning and can be used for implementing certain functionalities depending on the current state and the key that is being used.

These events that are triggered when a key is pressed are in the following order:

keydown Event: This event occurs when the user has pressed down the key. It will occur even if the key pressed does not produce a character value.
keypress Event: This event occurs when the user presses a key that produces a character value. These include keys such as the alphabetic, numeric, and punctuation keys. Modifier keys such as 'Shift', 'CapsLock', 'Ctrl' etc. do not produce a character, therefore they have no 'keypress' event attached to them.
keyup Event: This event occurs when the user has released the key. It will occur even if the key released does not produce a character value.

Note that different browsers may have different implementations of the above events. The onKeyDown, onKeyPress, and onKeyUp events can be used to detect these events respectively.

Example: The below example shows different events that get triggered when a key is pressed in their respective order.

HTML

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" 
          content="width=device-width, 
                   initial-scale=1.0">
    <title>Document</title>
</head>

<body>

    <body style="text-align:center;">
        <h1 style="color:green;">
            GeeksForGeeks
        </h1>

        <p>
            <b>onKeyPress Vs. onKeyUp
                and onKeyDown Events</b>
        </p>

        <input type="text" id="field" placeholder="Type here">
        <p id="status"></p>

        <script>
            // Script to test which key 
            // event gets triggered 
            // when a key is pressed
            let key_pressed =
                document.getElementById('field');

            key_pressed
                .addEventListener("keydown", onKeyDown);
            key_pressed
                .addEventListener("keypress", onKeyPress);
            key_pressed
                .addEventListener("keyup", onKeyUp);

            function onKeyDown(event) {
                document.getElementById("status")
                    .innerHTML = 'keydown: '
                    + event.key + '<br>'
            }
            function onKeyPress(event) {
                document.getElementById("status")
                    .innerHTML += 'keypress: '
                    + event.key + '<br>'
            }
            function onKeyUp(event) {
                document.getElementById("status")
                    .innerHTML += 'keyup: '
                    + event.key + '<br>'
            }
        </script>
    </body>
</body>

</html>

Output:

JavaScript onKeyPress onKeyUp and onKeyDown Events

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