Replace text between 2 tags with PHP

• How to replace text between 2 tags with PHP.
• Replace string between two points with PHP.
• Replacing string among two strings using preg_replace.

This function accepts 4 parameters. start point, end point, new text and the source. It replace the string between 2 points or tags.

Function

function replaceTags($startPoint, $endPoint, $newText, $source) {

    return preg_replace('#('.preg_quote($startPoint).')(.*)('.preg_quote($endPoint).')#si', '$1'.$newText.'$3', $source);
}

Calling The Function

$source='Untitled Document';
startPoint='< p>';
$endPoint='< /p>';
$newText='Welcome';

Output

< p>Welcome< /p>