使限制文本的功能不显示最后一个标点符号

I have this function that limits text, lets say to 50 chars like above:

$bio = limit_text($bio, 50);

function limit_text($text, $length){ // Limit Text
    if(strlen($text) > $length) {
        $text = substr($text, 0, strpos($text, ' ', $length));
    }
    return $text;
}

This should echo something like:

Hello, this is a text limited to 50 chars and it's a great ...

The problem is that the function shows the last punctuation mark which does not look professional. Like in this example:

Hello, this is a text limited to 50 chars and it has a comma at the end, ...

Is there any way to make the function not show the last punctuation mark?

Thank you!

<?php

$text="Hello, this is a text limited to 50 chars and it has a comma at the end.";

//$text = preg_replace("/[^a-zA-Z 0-9]+/", " ", $text); //bad
$text=rtrim($text,",.;:- _!$&#"); // good select what you want to remove


echo $text;

You could a function like this to parse the $text first:

$text = preg_replace("/[^a-zA-Z 0-9]+/", " ", $text);

This should get the job done, ctype_punct checks for all non-alphanumeric characters in a given string.

function limit_text($text, $length){ // Limit Text
    if(strlen($text) > $length) {
        $text = substr($text, 0, strpos($text, ' ', $length));
        if(ctype_punct(substr($text,-1))
            $text=substr($text,0,-1);
    }
    return $text;
}

return rtrim($text, ',') . '...'; // That is if you only care about the ',' character