OOP MySQLi Database Class

<?php
class database_mysqli {
 
	var $host = NULL;
	var $username = NULL;
	var $password = NULL;
	var $databaseName = NULL;
	var $link = NULL;
	var $queries = NULL;
	var $errors = NULL;
 
	function database_mysqli($host, $username, $password, $database) {
		$this->host = $host;
		$this->username = sha1($username);
		$this->password = sha1($password);
		$this->databaseName = $database;
		$this->link = "";
		$this->queries = array ();
		$this->errors = array ();
 
		$this->link = new mysqli($this->host, $username, $password, $database) or die("Could not connect to Database");
	}
 
	function justquery($sql) {
		$this->queries[] = $sql;
		return $this->link->query($sql);
	}
 
	function loadResult($sql) {
		if (!($cur = $this->justquery($sql))) {
			return null;
		}
		$ret = null;
		if ($row = $cur->fetch_row()) {
			$ret = $row[0];
		}
		mysqli_free_result( $cur );
		return $ret;
	}
 
	function loadFirstRow($sql) {
		if (!($cur = $this->justquery($sql))) {
			return null;
		}
		$ret = null;
		if ($row = $cur->fetch_object()) {
			$ret = $row;
		}
		mysqli_free_result( $cur );
		return $ret;
	}
 
	function insertid() {
		return $this->link->insert_id;
	}
 
	function query($sql, $key = "", $returns = true, $batch = false) {
		$sqls = $result = array ();
 
		switch ($batch) {
			default:
			case true:
				foreach ($sql as $index => $query) {
					$this->queries[] = $query;
					$answer = $this->link->query($query);
 
					if (!$answer) {
						$this->errors[] = $this->link->error;
					}
					else {
						if ($returns != false) {
							if ($answer->num_rows > 0){
								while ($row = $answer->fetch_object()) {
									if ($key != ""){
										$result[$index][$row->$key] = $row;
									}
									else {
										$result[$index][] = $row;
									}
								}
							} else {}
						} else {}
					}
				}
				break;
 
			case false:
				$this->queries[] = $sql;
				$answer = $this->link->query($sql);
 
				if (!$answer) {
					$this->errors[] = $this->link->error;
					$result = false;
				}
				else {
					if ($returns != false) {
						if ($answer->num_rows > 0){
							while ($row = $answer->fetch_object()) {
								if ($key != ""){
									$result[$row->$key] = $row;
								}
								else {
									$result[] = $row;
								}
							}
						} else {}
					}
					else {
						$result = true;
					}
				}
				break;
		}
 
		return $result;
	}
 
	function loadObject( $sql, &$object ) {
		if ($object != null) {
			if (!($cur = $this->justquery($sql))) {
				return false;
			} else {}
			if ($array = $cur->fetch_assoc()) {
				mysqli_free_result( $cur );
				$this->bindArrayToObject( $array, $object);
				return true;
			}
			else {
				return false;
			}
		}
		else {
			if ($cur = $this->justquery($sql)) {
				if ($object = $cur->fetch_object(W)) {
					mysqli_free_result( $cur );
					return true;
				}
				else {
					$object = null;
					return false;
				}
			}
			else {
				return false;
			}
		}
	}
 
	function bindArrayToObject( $array, &$obj) {
		if (!is_array( $array ) || !is_object( $obj )) {
			return (false);
		}
 
		foreach (get_object_vars($obj) as $k => $v) {
			if( substr( $k, 0, 1 ) != '_' ) {
				$ak = $k;
				if (isset($array[$ak])) {
					$obj->$k = $array[$ak];
				}
			}
		}
 
		return true;
	}
 
	function formatCSVCell($data) {
		$useQuotes = false;
 
		$quotable = array (
				"\"" => "\"\"",
				"," => ",",
				"\n" => "\n"
			);
 
		foreach ($quotable as $char => $repl) {
			if (eregi($char, $data)) {
				$useQuotes = true;
			} else {}
		}
 
		if ($useQuotes == true) {
			foreach ($quotable as $char => $repl) {
				$data = str_replace($char, $repl, $data);
			}
 
			$data = "\"" . $data . "\"";
		}
		else {
 
		}
 
		return $data;
	}
}
?>