Unfinished login manager

<?php
    class loginManager
    {

        /*
         * Class loginManager functions:
         * __construct(): Constructor. Pass the parameters of the MySQL connection variables and it will create the object and then calls mysqlConnect().
         * mysqlConnect(): Creates an OO connection to MySQL using the parameters passed.
         * mysqlQuery(): Sanitizes the SQL query by mysqlSanitize() and then runs it from the connection created using mysqlConnect().
         *      * Returns an 3D array where the first bracket is the row number. The second bracket is the column name.
         * mysqlSanitize(): Sanitizes the SQL Query passed as a parameter by using mysqli_real_escape_string().
         * returnMax(): Returns the greatest value of the parameters passed into the functions.
         */

        /*
         * Variables beginning with $database involve the database username, password, or host.
         */

        private $database_host = "";
        private $database_user = "";
        private $databate_pass = "";
        private $database_name = "";

        /*
         * Variables beginning with $sql involve SQL queries or connections.
         */

        private $sql_conn;

        function __construct()
        {
            //This constructor needs to be passed four parameters, the host, user, pass, and name of the db (in that order).

            switch (func_num_args())
            {
                case 4:
                    //If the number of parameters passed is correct, put them into an array.

                    $argarray = func_get_args();

                    /*
                     * (The above array)
                     * $argarray[0] = database host
                     * $argarray[1] = database username
                     * $argarray[2] = database password
                     * $argarray[3] = database name
                     */

                    //Next, set the variables that were passed as parameters.

                    $this->setHost($argarray[0]);
                    $this->setUser($argarray[1]);
                    $this->setPass($argarray[2]);
                    $this->setName($argarray[3]);

                    //Next, connect to the MySQL database with the previous information.

                    $this->mysqlConnect($this->database_host, $this->database_user, $this->database_pass, $this->database_name);
                    break;
                default:
                    //If there were not four parameters passed into the constructor, end the creation of it.

                    die("There were not four parameters passed into the constructor of the loginManager class. There were only " . func_num_args() . " passed.");
                    break;
            }
        }

        private function mysqlConnect($database_host, $database_user, $database_pass, $database_name)
        {
            //This function connects to a MySQL database.

            $this->sql_conn = new mysqli($database_host, $database_user, $database_pass, $database_name);

            if (mysqli_connect_error())
            {
                //If there was an error connecting, call the die function and close the connection.

                $this->sql_conn->close();
                die("mysqlConnect could not be completed: " . mysqli_connect_error());
            }
        }

        public function mysqlSanitize($string)
        {
            //This function will sanitize a string that was passed as a parameter and return it.

            return mysqli_real_escape_string($string);
        }

        public function mysqlQuery($query)
        {
            //Check and make sure the the $sql_conn variable is set.

            if (!isset($this->sql_conn))
            {
                //If the $sql_conn variable is not set, call the die function.

                die("You have not created a connection to a MySQL database.");
            }

            if (!is_string($query))
            {
                //If a string was not passed as a parameter, call the die function.

                die("An SQL query must be passed as a paramter int he mysqlQuery function.");
            }
            else
            {
                //If a string was passed as a parameter, then run the query.

                $resultarray = array();
                $result = $this->sql_conn->query($query);
                while ($row = $result->fetch_array())
                {
                    //As long as there are rows that matched the query, add to the array.

                    $resultarray[] = $row;
                }

                //Now, close the results and return the values.
                $result->close();
                return $resultarray;

                /*
                 * $resultarray[x][y]:
                 * [x] = the row number.
                 * [y] = the column name.
                 */
            }
        }

        public function returnMax()
        {
            //Create an array of the parameters passed.

            $argarray = func_get_args();

            //Create a blank variable that will later contain the largest variable.

            $largest = 0;

            //Loop through all of the parameters passed.

            foreach ($argarray as $value) {

                //Check if the value is an integer.

                if (!is_numeric($value))
                {
                    //If the current value is not a number, skip the value.

                    continue;
                }

                if (intval($value) > intval($largest))
                {
                    //If the new value is larger than the previous largest one, update it!

                    $largest = $value;
                }
            }
        }

        function setHost($var)
        {
            $this->database_host = $var;
        }

        function setUser($var)
        {
            $this->database_user = $var;
        }

        function setPass($var)
        {
            $this->database_pass = $var;
        }

        function setName($var)
        {
            $this->database_name = $var;
        }
    }

    $loginManager = new loginManager("127.0.0.1","root","", "logintest");
    $resultarray = $loginManager->mysqlQuery("SELECT * FROM users");
    echo $loginManager->returnMax(4,6,7,2);
?>