Php function calling

I have this function:

public function getCode($secret, $timeSlice = null)
{
    if ($timeSlice === null) {
        $timeSlice = floor(time() / 30);
    }

    $secretkey = $this->_base32Decode($secret);

    // Pack time into binary string
    $time = chr(0).chr(0).chr(0).chr(0).pack('N*', $timeSlice);
    // Hash it with users secret key
    $hm = hash_hmac('SHA1', $time, $secretkey, true);
    // Use last nipple of result as index/offset
    $offset = ord(substr($hm, -1)) & 0x0F;
    // grab 4 bytes of the result
    $hashpart = substr($hm, $offset, 4);

    // Unpak binary value
    $value = unpack('N', $hashpart);
    $value = $value[1];
    // Only 32 bits
    $value = $value & 0x7FFFFFFF;

    $modulo = pow(10, $this->_codeLength);

    return str_pad($value % $modulo, $this->_codeLength, '0', STR_PAD_LEFT);
}

that give me the 2FA code from the secret, but I don't know how to call the function on another page and how to config the $timeslice parameter. Thank you :)

In order to call the function from a different file you need to include or require the file before you can initiate the call. After which you can call the function (assuming you want 300 in your $timeSlice variable) like :

require 'functions_file.php';
$The_code = getCode("this is a secret", 300);

If the function is part of a class, you have to either instantiate the class like (assuming the class is named FunctionClass) :

require 'functions_file.php';
$Instantiated_Class = new FunctionClass();
$The_code = $Instantiated_Class->getCode("this is a secret", 300);

Or you can do :

require 'functions_file.php';
$The_code = FunctionClass::getCode("this is a secret", 300);