应用MYSQLI读取数据库读不了问题

[小白看世界OL]

<?php
  $DB_HOST = "";
  $DB_USER = "";
  $DB_PASSWORD = "";
  $DB_DATABASE = "";
  
  
  define("DB_HOST", "localhost");
  define("DB_USER", "root");
  define("DB_PASSWORD", "1234");
  
  define("DB_DATABASE", "t6_db_hp");

class mysqldb
  {
    var $host = DB_HOST;                   //localhost
    var $user = DB_USER;                   //root
    var $pass = DB_PASSWORD;               //1234
    var $database = DB_DATABASE;           //t6_db_hp
    var $conn;
    var $sql;
    var $n = 0;
    var $m = 0;
    var $result = "";
    var $debug = false;
    var $err = "";

function mysqldb($host="", $user="", $pass="", $database="")
	{
      if ($host != "") $this -> host = $host;
      if ($user != "") $this -> user = $user;
      if ($pass != "") $this -> pass = $pass;
      if ($database != "") $this -> database = $database;
	 
      if (!$this -> conn = @mysqli_connect($this -> host, $this -> user, $this -> pass))
	  {
        return $this -> output("连接数据库 '".$this -> host."' 失败。".mysqli_error($this -> conn));
      }
	   mysqli_query($this -> conn,"SET NAMES 'utf8'");
       $this -> selectdb();
    }

function selectdb($database="")
	{
      if ($database != "" && $database != $this -> database)
        $this -> database = $database;

      if (!mysqli_select_db($this -> conn, $this -> database))
	  {
        return $this -> output("无法使用数据库 '".$this -> database."'。");
      }
	}

function query($sql="", $database="")                     //$sql
	{
      if ($sql != "") $this -> sql = $sql;
      if ($database != "" && $database != $this -> database)
	  {
        $olddb = $this -> database;
        $this -> selectdb($database);
      }
      $this -> result = @mysqli_query($this -> conn,$this -> sql);
      if (mysqli_error($this -> conn) != "")
	  {
        return $this -> output("执行以下SQL语句时失败：'".$this -> sql."' <br><br>".mysqli_error($this -> conn));
      }
      $this -> n = @mysqli_affected_rows($this -> conn);           
        
      if (!empty($olddb)) $this -> selectdb($olddb);             
        return $this -> result;
		

	}

function get_data()
	{
   /*   if(!$this -> result || !preg_match("/^Resource/i", $this -> result)){    */        
        if(!$this -> result || !is_resource($this->result)){     
        return $this->output("没有数据，请先执行SQL的'select'语句!");
      }
      $count=0;
      $this -> m = @mysqli_num_rows($this -> result);
      if ($this -> m > 0)
	  {
        while ($row = mysqli_fetch_array($this -> result))
		{
          $data[$count] = $row;
          $count++;
        }
        return $this->result=$data;
      }
	  else
	  {
        return $this -> output("数据为空!");
      }
      mysqli_free_result($this -> result);
	}

function output($msg){
  $this->err=$msg;
  if ($this->debug)echo $msg;
  return false;
}
  }
?>
<?php /*?>////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////<?php */?>


<?php
$db = new mysqldb();
if($db)
{
	echo "链接数据库 1";
	echo "<br/>";
	echo "<br/>";
	}

 $sql = "SELECT * FROM t6_dept where de_id>'0' ORDER BY de_id ASC";
 $db -> query($sql);
 $result = $db -> get_data();
 
if(!$result)
       {
	echo "取出数据失败result 0";
	echo "<br/>";
	echo "<br/>";
	}

echo $result[0]["de_name"];          //无法显示数据

print_r($db);

?>

最后输出不了数据$resul没有值 t浏览器显示结果：求哪里出错了 ？？？

链接数据库 1

取出数据失败result 0

mysqldb Object ( [host] => localhost [user] => root [pass] => 1234 [database] => t6_db_hp [conn] => mysqli Object ( [affected_rows] => 4 [client_info] => mysqlnd 5.0.11-dev - 20120503 - $Id: f373ea5dd5538761406a8022a4b8a374418b240e $ [client_version] => 50011 [connect_errno] => 0 [connect_error] => [errno] => 0 [error] => [error_list] => Array ( ) [field_count] => 4 [host_info] => localhost via TCP/IP [info] => [insert_id] => 0 [server_info] => 5.6.20 [server_version] => 50620 [stat] => Uptime: 22428 Threads: 1 Questions: 5 Slow queries: 0 Opens: 68 Flush tables: 1 Open tables: 61 Queries per second avg: 0.000 [sqlstate] => 00000 [protocol_version] => 10 [thread_id] => 1 [warning_count] => 0 ) [sql] => SELECT * FROM t6_dept where de_id>'0' ORDER BY de_id ASC [n] => 4 [m] => 0 [result] => mysqli_result Object ( [current_field] => 0 [field_count] => 4 [lengths] => [num_rows] => 4 [type] => 0 ) [debug] => [err] => 没有数据，请先执行SQL的'select'语句! )

[xuzuning]

mysqli_query($this -> conn,$this -> sql) 返回的是 mysqli_result 对象，不是 resource （资源） 所以 !is_resource($this->result) 成立，程序提前结束

[小白看世界OL]

引用

mysqli_query($this -> conn,$this -> sql) 返回的是 mysqli_result 对象，不是 resource （资源） 所以 !is_resource($this->result) 成立，程序提前结束

要怎么改？？？

[xuzuning]

if(!$this -> result || !is_object($this->result)){ return $this->output("没有数据，请先执行SQL的'select'语句!"); }

[小白看世界OL]

引用

if(!$this -> result || !is_object($this->result)){ return $this->output("没有数据，请先执行SQL的'select'语句!"); }

终于解决了困扰很多天的问题了，谢谢版主

[kkg_1473995421]

应用MySql读取数据库数据示例 //连接数据库conn文件夹 <?php $conn=mysql_connect("localhost","root","root"); //连接数据库服务器 mysql_select_db("db_forumm",$conn); //连接指定的数据库 mysql_query("set names gb2312"); //对数据库中的编码格式进行转换,避免出现中文乱码的问题 ?> //引入连接数据库文件 <?php include("../conn/conn.php");?> //读取数据库信息 <?php if($page){ $page_size=4; //每页显示2条记录 $query="select count(*) as total from tb_forum_user where tb_forum_id"; //从数据库中读取数据 $result=mysql_query($query);//CodeGo.net/ $message_count=mysql_result($result,0,"total"); //获取总的记录数 $page_count=ceil($message_count/$page_size); //获取总的页数 $offset=($page-1)*$page_size; $query=mysql_query("select * from tb_forum_user where tb_forum_id order by tb_forum_id desc limit $offset, $page_size"); while($myrow=mysql_fetch_array($query)){ ?> //显示数据库信息 <?php echo $myrow[tb_forum_name];?>" ><?php echo $myrow[tb_forum_name];?></a></span></td> <td align="center"><span class="STYLE1"><?php echo $myrow[tb_forum_truepass];?></span></td> <td align="center"><span class="STYLE1"><?php echo $myrow[tb_forum_date];?></span></td> <td align="center"><span class="STYLE1"><?php echo $myrow[tb_forum_type];?></span></td> <td align="center"><a href="delete_leaguer.php?delete_id=<?php echo $myrow[tb_forum_id];?>&&delete_user=<?php echo $myrow[tb_forum_user];?>" //分页显示（略）