PHP字符串按长度分割方法_PHP定长分割技巧

$str = "abcdefghij";
$chunks = str_split($str, 4);
print_r($chunks);
// 输出：
// Array
// (
//     [0] => abcd
//     [1] => efgh
//     [2] => ij
// )

$str = "你好世界abcdef";
$chunks = mb_str_split($str, 4, 'UTF-8');
print_r($chunks);
// 按4个字符一组（支持中文），输出：
// Array
// (
//     [0] => 你好世
//     [1] => 界abc
//     [2] => def
// )

$chunks = preg_split('/(?<=\G.{4})/u', $str, -1, PREG_SPLIT_NO_EMPTY);

function mb_str_split_custom($str, $length = 1, $encoding = 'UTF-8') {
    $len = mb_strlen($str, $encoding);
    $chunks = [];
    for ($i = 0; $i < $len; $i += $length) {
        $chunks[] = mb_substr($str, $i, $length, $encoding);
    }
    return $chunks;
}

// 使用示例
$str = "一二三四五六七八";
$result = mb_str_split_custom($str, 3);
print_r($result);
// 输出每3个中文字符一组