src (HTML attribute)

The src attribute in HTML specifies the location of an embedded resource, most commonly images, but also applicable to audio, video, and iframes. This location can be relative to the current webpage, relative to the server's root directory, or a complete URL.

Relative Paths:

• Same Directory: <img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/000/174052993373573.jpg" class="lazy" alt="src (HTML attribute) "> (image.jpg is in the same folder as the HTML file).
• One Level Up: <img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/000/174052993391833.jpg" class="lazy" alt="src (HTML attribute) "> (image.jpg is one directory above the current HTML file).
• Within Website Root: <img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/000/174052993464780.jpg" class="lazy" alt="src (HTML attribute) "> (image.jpg is in the /images folder at the website's root).

Absolute URLs:

For images hosted on a different server, use a full URL: <img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/000/174052993538767.jpg" class="lazy" alt="Image Description">.

Example:

The following code displays an image named myimage.png located in the same directory as the HTML file:

<code class="language-html"><img src="/static/imghwm/default1.png" data-src="https://img.php.cn/upload/article/000/000/000/174052995196248.png" class="lazy" alt="src (HTML attribute) "></code>

Key Considerations:

• alt Attribute: Always include the alt attribute to provide alternative text for screen readers and when the image fails to load. This is crucial for accessibility.
• File Types: The src attribute should accurately reflect the file type (e.g., .jpg, .png, .gif, .mp4, .mp3).
• Error Handling: If the specified resource isn't found, the browser will typically display a broken image icon or nothing at all. Proper error handling might involve alternative image sources or fallback mechanisms.
• Security: Embedding resources from different domains can be subject to browser security policies (CORS).

Frequently Asked Questions (FAQs):

While the provided text covers many aspects of the src attribute, here's a concise summary addressing key points:

• What is src? src (source) specifies the URL of an embedded resource.
• Which tags use src? <img alt="src (HTML attribute)" >, <audio></audio>, <video></video>, <iframe></iframe>, and others embedding external content.
• What happens if src is missing? The image (or other embedded resource) won't display.
• Can src handle different domains? Yes, but subject to CORS restrictions.
• Multiple sources? Use <source></source> elements within <picture></picture>, <audio></audio>, or <video></video> tags for multiple sources.
• Relative vs. Absolute URLs? Relative URLs are relative to the current page; absolute URLs are complete URLs.
• src vs. href? src embeds content; href creates a link to content.
• Maximum file size? No strict limit, but larger files impact loading times.
• HTTPS to HTTP? Not recommended due to security risks (mixed content warnings).

This revised answer provides a more streamlined explanation and addresses the FAQs in a clearer, more concise manner.

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