php实现将字符串分割的方法

= 0;) { $new_str = ""; for ($j = $i; $j > $i - 3 && $j >= 0; $j --) { $new_str .= $str[$j]; } $arr[] = $new_str; $i = $j; } $string = implode(',', $arr); // 翻转字符串自己实现 // $string = strrev($string); for ($i = 0, $j = strlen($string) - 1; $i <= $j; $i ++, $j --) { $tmp = $string[$i]; $string[$i] = $string[$j]; $string[$j] = $tmp; } return $string; } $str = "1234567890"; $new_str = splitStrWithComma($str); echo $new_str . "\n";