When extracting specific data from a website using regular expressions in PHP, what initial steps do you take to analyze the source code?

When extracting specific data from a website using regular expressions in PHP, the initial step is to analyze the source code of the webpage to identify the pattern or structure of the data you want to extract. This involves inspecting the HTML source code of the webpage to understand how the data is formatted and where it is located within the markup. Once you have identified the pattern, you can use regular expressions in PHP to extract the desired data based on that pattern.

<?php
// Get the HTML source code of the webpage
$html = file_get_contents('https://example.com');

// Define the regular expression pattern to extract specific data
$pattern = '/<h1>(.*?)<\/h1>/'; // Example pattern to extract data within <h1> tags

// Use preg_match() function to extract data based on the pattern
if (preg_match($pattern, $html, $matches)) {
    // Display the extracted data
    echo "Extracted data: " . $matches[1];
} else {
    echo "No data found";
}
?>