当字符串包含数字时，Preg_replace不起作用

So i have a string with flags like this: <<-- name -->> and now I want to replace all of them for ''.

I made the following function:

function removeFlags($output) {
    $output = preg_replace('/\<<--[^-->>]+-->>/', '', $output);
    return $output;
}

It works fine for the most flags but not when they contain numbers. For example: <<-- Model -->> will just be replaced for '', but <<-- 360 -->> will not be removed.

What am I doing wrong?

This should work for you, as you want to replace anything that is preceded and succeeded by a certain pattern

$output = preg_replace('/\<<--.+?-->>/', '', $output);

And I think your pattern should have worked for numbers as well, but do the numbers have a space before and after them?

This pattern works:

$output = preg_replace('/\<<--[^.]+-->>/', '', $output);

The hyphen - inside a character class indicates a range. You are accidentally negating a range from - to > which contains digits 0-9 so it can not match <<-- 360 -->>

To match a hyphen literally, put it at start or end of the class or escape it with a backslash.
Also you need to add only one of the different characters to the character class.

<<--[^>-]+-->>

See demo at regex101