php replacing string error

Question

I am trying to delete a string from a string, but the result of strstr is not finding the string. I will try to be as clear as I can here....

The problem is strpos() is not finding $deletTabHTML. I have alerted it in ajax and it is exactly the same as a line in the commonHTML, but obviously it isn't for some reason I cannot figure out. I am assuming I am missing something 'invisible'? My script works if I hardcode the html to be deleted, so the overall script works.

here is the php:

$commonHTML = file_get_contents($url);
if (!empty($_POST['action']) && $_POST['action'] == 'deleteTab') {
    $deletTabHTML = trim($_POST['theHTM']);
    if(strpos($commonHTML, $deletTabHTML) !== false) {
        $is_deleted="deleted";
    }else{
        $is_deleted="NOT deleted, ERROR:".$deletTabHTML;
    }
    echo '{"is_deleted":"' . $is_deleted . '"}';
    return;
}

MORE INFO: jQuery is getting an element from the dom and sending it to a php script which is opening a file and deleting the element:

<li id="contact"><a href="#contact" rel="ajax">Contact</a></li>

The data returned to ajax is:

<li id="contact"><a href="#contact" rel="ajax">Contact</a></li>

but for some reason it is not finding it. Thos were copied and pasted from the actual file and a javascript alert. They look exactly the same.

I hope that is enough info.

Answer 1

strpos is case sensitive

Try

stripos()

Answer 2

Aside from attempting to make the text search case insensitive, you also might want to make sure that it contains no unicode characters by using utf8_decode() on it first.

Lastly, it couldn't hurt to do some sanity checks on $_POST['theHTM'] before attempting to use it. (It looks like it's missing an L at the end, but it's also worth using isset() to verify that it actually exists.)