Simple: How to replace “all between” with php? [duplicate]

Answer 1

If you don't know what's inside the tag, it's possible there is another tag in there e.g.

somethingsomething else

And so a generic string replace function won't do the job.

A more robust solution is to treat the string as XML and manipulate it with DOMDocument. Admittedly this only works if the string is valid as XML, but I still think it's a better solution than a string replace.

$string = "i don't know what is here";
$replacement = "replacement";

$doc = new DOMDocument();
$doc->loadXML($str1);
$node = $doc->getElementsByTagName('tag')->item(0);
$newNode = $doc->createElement("tag", $replacement); 
$node->parentNode->replaceChild($newNode, $node);
echo $str1 = $doc->saveHTML($node); //output: replacement