What are the different methods suggested in the PHP forum thread for extracting the first 20 characters of a string without cutting off in the middle of a word?

When extracting the first 20 characters of a string in PHP, it is important to ensure that the extraction does not cut off in the middle of a word. One way to solve this issue is to check if the 21st character is a space, and if not, backtrack to the nearest space before it to avoid cutting off in the middle of a word.

function extractFirst20Chars($string) {
    if(strlen($string) <= 20) {
        return $string;
    }
    
    $substring = substr($string, 0, 20);
    if($string[20] != " ") {
        $lastSpace = strrpos($substring, " ");
        $substring = substr($substring, 0, $lastSpace);
    }
    
    return $substring;
}

// Example usage
$string = "This is a sample string that needs to be extracted";
echo extractFirst20Chars($string);