How Can I Extract the Source URL of the First Image from an HTML Document Using Parsing Techniques?

Retrieving Source URLs of HTML Image Tags Using Parsing Techniques

Retrieving dynamic content, such as the source URL for the first occurring image tag within an HTML document, is a common task in web development. To achieve this, HTML parsing techniques like DOMDocument and DOMXpath come into play.

DOMDocument and DOMXpath

DOMDocument represents an HTML document as a tree structure, enabling access to its elements and attributes. DOMXpath provides an efficient way to traverse this tree and extract specific values.

Solution Using DOMDocument and DOMXpath

• Load the HTML document into a DOMDocument object.
• Create a DOMXPath object associated with the DOMDocument.
• Use an XPath expression to retrieve the source URL of the first image tag (//img/@src).
• Assign the retrieved URL to a variable.

Example

$html = '<img border="0" src="/images/image.jpg" alt="Image" width="100" height="100" />';

$doc = new DOMDocument();
$doc->loadHTML($html);
$xpath = new DOMXPath($doc);
$src = $xpath->evaluate("string(//img/@src)");

Retrieving the First Image's Source

To ensure that only the source URL of the first image is obtained, use the string(//img/@src) XPath expression. This expression returns the source URL as a string.

One-Liner Solution

For a more compact solution, you can use the following one-liner:

$src = (string) reset(simplexml_import_dom(DOMDocument::loadHTML($html))->xpath("//img/@src"));

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