在PHP中加密字符串，其中输出是URL安全的

I have a requirement where I need to move a string from one place to another via GET. e.g. example.com?string=ENCRYPTED_STRING

Is there a algorithm or some other method to encrypt the string so it is URL safe?

By that I mean it will not have characters like = or & ...

I have tried openssl with AES-256-CBC but no luck.

The data is not overly very sensitive but I would prefer to obfuscate it in someway.

The code below allow you to encrypt (alpha/num) and decrypt a string. But you need Mcrypt php module installed to make it run.

static public function encrypt($text){
    $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);                                                                           
    $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
    $key = "useasuperkey";

    return (bin2hex(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_ECB, $iv)));
}

static public function decrypt($text){
    $len = strlen($text);  
    $text = pack("H" . $len, $text);
    $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);                                                                           
    $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
    $key = "useasuperkey";

    return trim(mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_ECB, $iv));
}

Oh hey, I've actually done this in one of my applications. My code looks a lot different (because of my custom tools, it's a one-liner), but works basically like this (uses defuse/php-encryption):

use \Defuse\Crypto\Crypto;

$url = "/my/endpoint?".http_build_query([
    'something' => base64_encode(
        Crypto::encrypt('my_secret_info', CRYPTO_SECRET_KEY)
    )
]);
// Then you can either use $url in header('Location: '.$url) or in an HTML link safely.