封装mysql类

class Mysql {private $host;private $user;private $pwd;private $dbName;private $charset;private $conn = null;public function __construct() {$this->host = 'localhost';$this->user = 'root';$this->pwd = 'root';$this->dbName = 'test';$this->connect($this->host,$this->user,$this->pwd);$this->switchDb($this->dbName);$this->setChar($this->charset);}//负责链接private function connect($h,$u,$p) {$conn = mysql_connect($h,$u,$p);$this->conn = $conn;}//负责切换数据库public function switchDb($db) {$sql = 'use' . $db;$this->query($sql);}//负责设置字符集public function setChar($char) {$sql = 'set names' . $char;$this->query($sql);}//负责发送sql查询public function query($sql) {return mysql_query($sql,$this->conn);}//负责获取多行多列的select结果public function getAll($sql) {$list = array();$rs = $this->query($sql);if (!$rs) {return false;}while ($row = mysql_fetch_assoc($rs)) {$list[] = $row;}return $list;}public function getRow($sql) {$rs = $this->query($sql);if(!$rs) {return false;}return mysql_fetch_assoc($rs);}public function getOne($sql) {$rs = $this->query($sql);if (!$rs) {return false;}return mysql_fetch_assoc($rs);return $row[0];}public function close() {mysql_close($this->conn);}}echo '<pre>';$mysql = new Mysql();print_r($mysql);$sql = "insert into stu values (4,'wangwu','99998')";if($mysql->query($sql)){echo "query成功";}else {echo "失败";}echo "<br />";$sql = "select * from stu";$arr = $mysql->getAll($sql);print_r($arr);