Remove white space characters on both sides (rim function cannot remove half width spaces)

How to display the text entered by the user

This is a user input copied from a database. First of all, it is not rich text, but it should be displayed in a beautiful format (roast).

phpHow to handle characters?

$intro_ arr=explode("\n",$str); // Split into arrays based on line breaks
$new_str = '';
foreach($intro_arr as $item) {
    //Exclude white space characters
    if(!empty($item)){
        //Remove blank characters on both sides? The trim function cannot remove half width spaces.
        $item = mb_ ereg_ replace('^(　| )+','', $item);// Remove left margin
        $item = mb_ ereg_ replace('(　| )+$','', $item);// Remove right margin

        //Set of labels,,
        $item_p = '<p style="text-indent:2em;">'.trim($item).'</p>';
        $new_str .= $item_p;
    }
}

This work adoptsCC agreement, reprint must indicate the author and the link to this article