php實現mysql封裝類示例

<?php   
 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);
 }
  //負責連接
 private function connect($h,$u,$p) {
  $conn = mysql_connect($h,$u,$p);
  $this->conn = $conn;
 }
  //負責切換數據庫
 public function switchDb($db) {
  $sql = 'use' . $db;
  $this->query($sql);
 }
  //負責設置字符集
 public function setChar($char) {
  $sql = 'set names' . $char;
  $this->query($sql);
 }
  //負責發送sql查詢
 public function query($sql) {
  return mysql_query($sql,$this->conn);
 }
  //負責獲取多行多列的select結果
 public function getAll($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);
 $sql = "insert into stu values (4,'8023','99998')";
 if($mysql->query($sql)){
 echo "query成功";
}else {
 echo "失敗";
}
 echo "<br />";
 $sql = "select * from stu";
$arr = $mysql->getAll($sql);
 print_r($arr);
?>