php Control character error, possibly incorrectly encoded ?

// $s='{"test":"json"}';
$s='{"test":"    json"}';//json前面有個(gè)占一個(gè)長(zhǎng)度的不可見(jiàn)字符 好像保存后 sf 處理成空格了，點(diǎn)擊編輯可以看到 一個(gè)復(fù)制出來(lái)的字符 http://ascii-code.com/ http://stackmirror.bird.so/page/s1dxa25hkmd4 http://stackmirror.bird.so/page/467s1u1mvxx JSON.stringify(s)顯示是 `\t`
echo '<pre>';echo PHP_EOL;

print_r(json_decode($s,1));
print_r(json_last_error_msg());//Control character error, possibly incorrectly encoded
echo PHP_EOL;
switch (json_last_error()) {
        case JSON_ERROR_NONE:
            echo ' - No errors';
        break;
        case JSON_ERROR_DEPTH:
            echo ' - Maximum stack depth exceeded';
        break;
        case JSON_ERROR_STATE_MISMATCH:
            echo ' - Underflow or the modes mismatch';
        break;
        case JSON_ERROR_CTRL_CHAR:
            echo ' - Unexpected control character found';
        break;
        case JSON_ERROR_SYNTAX:
            echo ' - Syntax error, malformed JSON';
        break;
        case JSON_ERROR_UTF8:
            echo ' - Malformed UTF-8 characters, possibly incorrectly encoded';
        break;
        default:
            echo ' - Unknown error';
        break;
    }
//輸出 - Unexpected control character found

目前找到一個(gè)方案，來(lái)自 json_decode 無(wú)法解析，那就試試 Services_JSON

include 'JSON.php';//https://github.com/pear/Services_JSON
$json = new Services_JSON(SERVICES_JSON_LOOSE_TYPE);
$data = $json->decode($s);

function strip_control_characters($str){
    return preg_replace('/[\x00-\x1F\x7F-\x9F]/u', '', $str);
}