Get Elements of a Specific Class Inside a Div in JavaScript

You can select elements with a specific class inside a <div> using JavaScript DOM methods. This allows you to target only the matching elements within a particular container.

• Use querySelectorAll() to select all elements matching a CSS selector.
• Call querySelectorAll() on the <div> to limit the search to that container.
• Loop through the selected elements to access or modify them.

Approach: Using querySelectorAll()

The querySelectorAll() method returns all elements that match a specified CSS selector. First, select the <div> element and then use .querySelectorAll() with the required class selector.

Syntax:

element.querySelectorAll(".className");

Example: Selects all elements with the example1 class inside the <div> and changes their background color when the button is clicked.

<!DOCTYPE html>
<html>

<head>
    <style>
        #tag {
            border: 4px solid black;
            margin: 5px;
            padding: 10px;
        }
    </style>
</head>

<body>

    <div id="tag">
        <p class="example1">HTML</p>
        <p class="example1">CSS</p>
        <p class="example1">JavaScript</p>
        <p class="example2">C</p>
    </div>

    <br>

    <button onclick="changeColor()">
        Click to Apply Change
    </button>

    <script>
        function changeColor() {
            const elements = document
                .getElementById("tag")
                .querySelectorAll(".example1");

            elements.forEach(function (element) {
                element.style.backgroundColor = "blue";
            });
        }
    </script>

</body>

</html>

After clicking the Click to Apply Change button, the elements containing HTML, CSS, and JavaScript have their background color changed, while the element containing C remains unchanged.

Output: