How to hide span element if anchor href attribute is empty using JavaScript?

Javascript Web Development Front End Technology

In modern web development, it's often necessary to dynamically hide or show elements based on certain conditions. One common requirement is to hide a element if the associated <a> (anchor) element has an empty href attribute. This functionality can be particularly useful when working with navigation menus or links that are generated dynamically.

In this article, we'll explore how to achieve this behavior using JavaScript. We'll delve into two different approaches: one utilizing JavaScript event listeners, and the other leveraging CSS selectors. By understanding both methods, you'll have the flexibility to choose the one that best suits your project requirements.

So, let's dive in and learn how to hide a element if the href attribute of its associated <a> element is empty.

Understanding the Problem

Before we dive into the solutions, let's gain a clear understanding of the problem at hand. We want to hide a element if the href attribute of its associated <a> element is empty. This means that when the user interacts with the webpage, if there is no link associated with a particular <a> element, the corresponding element should be hidden.

To achieve this, we need to −

Identify the <a> elements that need to be checked.
Access the href attribute of each <a> element.
Determine if the href attribute is empty or not.
Hide or show the corresponding element based on the result.

Next, we'll discuss the first technique: using JavaScript event listeners to hide the element.

Technique 1: Using JavaScript Event Listeners

In this technique, we'll use JavaScript event listeners to monitor changes in the <a> elements and hide or show the corresponding element based on the href attribute.

Steps

Select all the <a> elements on the page using document.querySelectorAll('a').
Iterate over the selected elements using a loop.
Attach a click event listener to each <a> element.
In the event listener callback function, check if the href attribute of the clicked <a> element is empty (href === '').
If the href is empty, hide the associated element by setting its display property to none. Otherwise, show the element by setting its display property to an appropriate value (e.g., block or inline).

Example

<!DOCTYPE html>
<html>
<head>
   <title>Hide Span on Empty Href</title>
   <style>
      /* Styles for demonstration purposes */
      .hidden {
         display: none;
      }
   </style>
</head>
<body>
   <a href="#">Link 1</a>
   <span>Associated Span 1</span>
   <br>
   <a href="">Link 2</a>
   <span>Associated Span 2</span>
   <br>
   <a href="https://example.com">Link 3</a>
   <span>Associated Span 3</span>   
   <script>
      // Select all <a> elements
      const links = document.querySelectorAll('a');
      
      // Attach event listener to each <a> element
      links.forEach((link) => {
         link.addEventListener('click', function(event) {
            // Check if href is empty
            if (link.href === '') {
               // Hide the associated <span> element
               link.nextElementSibling.style.display = 'none';
            } else {
               // Show the associated <span> element
               link.nextElementSibling.style.display = '';
            }
         });
      });
   </script>
</body>
</html>

In this example, we have three <a> elements with corresponding elements. When a user clicks on an <a> element, the associated element will be hidden if the href attribute is empty. Otherwise, the element will be shown.

Next, we'll explore the second technique: using CSS selectors to hide the element.

Technique 2: Using CSS Selectors

In this technique, we'll leverage CSS selectors to target and hide the elements based on the condition of the associated <a> elements' href attribute.

Steps

Define a CSS selector that targets the elements to be hidden when the href attribute of their associated <a> elements is empty.
Use the :empty pseudo-class in the CSS selector to select the <a> elements with empty href attributes.
Specify the desired CSS properties to hide the selected elements. For example, you can set the display property to none or use other CSS properties like visibility or opacity to achieve the desired hiding effect.

Example

<!DOCTYPE html>
<html>
<head>
   <title>Hide Span on Empty Href</title>
   <style>
      /* Styles for demonstration purposes */
      .hidden {
         display: none;
      }
      
      /* CSS selector to target the <span> elements */
      a[href=""]:empty + span {
         display: none;
      }
   </style>
</head>
<body>
   <a href="#">Link 1</a>
   <span>Associated Span 1</span>
   <br>
   <a href="">Link 2</a>
   <span>Associated Span 2</span>
   <br>
   <a href="https://example.com">Link 3</a>
   <span>Associated Span 3</span>
</body>
</html>

In this example, we have three <a> elements with corresponding elements. By using the CSS selector a[href=""]:empty + span, we target the elements that immediately follow <a> elements with empty href attributes. We then set the display property of those elements to none to hide them.

Comparisons

Both techniques discussed in this article provide solutions to hide elements when the associated <a> elements have empty href attributes. However, they differ in their implementation and usage scenarios. Let's compare them based on a few aspects −

Complexity and Dependencies

JavaScript Event Listeners − This technique requires writing JavaScript code to attach event listeners to the <a> elements and manipulate the visibility of the associated elements. It involves more code and dependencies on JavaScript.
CSS Selectors − This technique utilizes CSS selectors to target and style the elements based on the condition of the <a> elements' href attributes. It is purely CSS-based and does not require any additional JavaScript code.

Flexibility and Dynamism

JavaScript Event Listeners − With JavaScript, you have more flexibility to handle dynamic changes in the DOM. You can dynamically attach and remove event listeners, making it suitable for scenarios where the <a> elements or their href attributes may change dynamically.
CSS Selectors − CSS selectors are applied statically and are not aware of dynamic changes in the DOM. If the <a> elements or their href attributes change dynamically, the CSS selector may not automatically update the visibility of the elements.

Browser Support

JavaScript Event Listeners − JavaScript event listeners are widely supported across modern browsers and provide reliable cross-browser compatibility.
CSS Selectors − CSS selectors are well-supported by modern browsers, but older browsers may have limited support for some advanced selectors or pseudo-classes. Make sure to check the compatibility requirements of your target audience.

Flexibility and Dynamism

JavaScript Event Listeners − JavaScript event listeners involve runtime execution of code, which may have a slight impact on performance, especially when dealing with a large number of elements or frequent DOM updates.
CSS Selectors − CSS selectors are highly optimized by browsers and can provide efficient element selection and styling. They generally offer better performance compared to JavaScript-based solutions.

Consider these factors when choosing the appropriate technique for your specific use case.

Conclusion

In this article, we discussed how to hide elements when the associated <a> elements have empty href attributes. We explored two techniques: using JavaScript event listeners and utilizing CSS selectors.

By using JavaScript event listeners, we can dynamically monitor the state of the <a> elements and hide the associated elements based on the condition of their href attributes. This approach provides flexibility and control, especially in scenarios with dynamic updates.

On the other hand, CSS selectors offer a purely CSS-based solution, leveraging selectors like :empty to directly target and hide elements associated with empty href attributes. This approach is simple and lightweight, requiring no additional JavaScript code.

Mrudgandha Kulkarni

Updated on: 07-Aug-2023

1K+ Views

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