给你:

function neat_trim($str, $n, $delim='…') {
   $len = strlen($str);
   if ($len > $n) {
       preg_match('/(.{' . $n . '}.*?)\b/', $str, $matches);
       return rtrim($matches[1]) . $delim;
   }
   else {
       return $str;
   }
}

我知道这很旧，但是…

function _truncate($str, $limit) {
    if(strlen($str) < $limit)
        return $str;
    $uid = uniqid();
    return array_shift(explode($uid, wordwrap($str, $limit, $uid)));
}

当我注意到wordwrap函数的$break参数时，产生了以下解决方案:

字符串$str [， int $width = 75[，字符串$break = "\n" [， bool $cut = false]])

下面是解决方案:

/**
 * Truncates the given string at the specified length.
 *
 * @param string $str The input string.
 * @param int $width The number of chars at which the string will be truncated.
 * @return string
 */
function truncate($str, $width) {
    return strtok(wordwrap($str, $width, "...\n"), "\n");
}

示例# 1。

print truncate("This is very long string with many chars.", 25);

上面的例子将输出:

This is very long string...

例# 2。

print truncate("This is short string.", 25);

上面的例子将输出:

This is short string.

我是这样做的:

$string = "I appreciate your service & idea to provide the branded toys at a fair rent price. This is really a wonderful to watch the kid not just playing with variety of toys but learning faster compare to the other kids who are not using the BooksandBeyond service. We wish you all the best";

print_r(substr($string, 0, strpos(wordwrap($string, 250), "\n")));

function trunc($phrase, $max_words) {
       $phrase_array = explode(' ',$phrase);
       if(count($phrase_array) > $max_words && $max_words > 0)
          $phrase = implode(' ',array_slice($phrase_array, 0, $max_words)).'...';
       return $phrase;
    }

我创建了一个更类似于substr的函数，并使用了@Dave的思想。

function substr_full_word($str, $start, $end){
    $pos_ini = ($start == 0) ? $start : stripos(substr($str, $start, $end), ' ') + $start;
    if(strlen($str) > $end){ $pos_end = strrpos(substr($str, 0, ($end + 1)), ' '); } // IF STRING SIZE IS LESSER THAN END
    if(empty($pos_end)){ $pos_end = $end; } // FALLBACK
    return substr($str, $pos_ini, $pos_end);
}

注:全长切割可能小于substr。