php while循环退不出是什么有关问题

<?php <br />include('include/config.php');<br />include('include/dbclass.php');<br />session_start();<br /><br /><br />$db = db::getInstance();  <br /> //  $db->check_user_login();   //检查用户是否登录<br />$db->createcon();            //建立连接<br />// $user=$_SESSION["user"];<br />$user = "libero";           //测试临时使用<br />//   执行 user数据表 选取user数据<br />$sql_user = "select * from user where user = '$user'";<br />$user_array  = $db->fetch_array($sql_user);<br /><br /><br /><br /><br />//  执行 yytable 数据  获取 yytable 所有数据<br />$sql_yytable = "select * from yytable where uid = '$user_array[0]'";<br /><br />echo "<table border = '1'>" ;<br /><br />while($yytable_array = $db->fetch_array($sql_yytable)){<br />	echo "<tr>";<br />	echo "<td>".$yytable_array[0]."</td>";<br />	echo "<td>".$yytable_array[1]."</td>";<br />	echo "<td>".$yytable_array[2]."</td>";<br />	echo "<td>".$yytable_array[3]."</td>";<br />	echo "<td>".$yytable_array[4]."</td>";<br />	echo "<td>".$yytable_array[5]."</td>";<br />	<br />	<br />	echo "</tr>";<br />	}<br /><br /><br /><br />echo "</table>";<br /><br />//dbclass<br /><br /><?php <br />class db{<br />	private static $dbhost = "localhost";<br />	private static $dbuser = "root";<br />	private static $password = "";<br />	private static $dbname = "yy";<br />	private static $instance = NULL;<br />	 <br />	 <br />	 // 构造函数<br />	private function _construct(){}<br />     //  实例化<br />		public static function getInstance(){<br />			if (self::$instance == null){<br />				self::$instance = new db();<br />				}<br />			return self::$instance;<br />			    }<br />	//连接数据库<br />	public function mycon(){<br />		@mysql_connetc(self::$dbhost,self::$dbuser,self::$password);<br />		<br />		}<br />	//选择数据库	<br />	public function selectdb(){<br />		$mysql_select_db(self::$dbname);<br />		<br />		}<br />				<br />    //创建连接  连接数据库<br />	public function createcon(){<br />		<br />		mysql_connect(self::$dbhost,self::$dbuser,self::$password);<br />		mysql_select_db(self::$dbname);<br />	}<br />		<br />		<br />		//  根据查询条件获取 $sql 结果集<br />	public function fetch_array($sql){<br />		   <br />		   if($result = $this->query($sql))<br />		  {<br />		  $rs = mysql_fetch_array($result, MYSQL_BOTH);<br />		   return $rs;<br />		   <br />		   }<br />		else { echo "数据查询失败"; }<br />		<br />		}<br />		<br />		// 数据库查询执行语句<br />	public function query($sql){<br />		mysql_query("set names utf8");<br />		return mysql_query($sql);<br />	}<br />	<br />	//   loop 更具结果集 获取数组<br />	<br />	public function loop_query($result){<br />		return mysql_fetch_array($result);<br />		<br />		<br />		}<br />	<br />	<br />	<br />	<br />		//关闭数据库连接<br />		<br />		public function close(){<br />			<br />			return mysql_close();	<br />		<br />		}	<br />		<br />	<br />			<br />			}<br />		<br />		<br />		<br />		<br />		<br />		<br />		<br />				<br />		}<br />	<br />	<br />	<br />       <br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br />?><br /><br /><br />

<br>  public function fetch_all($sql){<br>    if($result = $this-&gt;query($sql))<br>    {<br>      while($r = mysql_fetch_array($result, MYSQL_BOTH)) {<br>        $res[] = $r;<div class="clear"></div>