PHP PDO 连接数据库

<?php
/**
 * 声明一个数组存放数据库链接信息
 */
 $C = array();

/**
 * 在数据库链接信息数组中存放相关信息
 */
 $C[‘DB_HOST‘] = ‘localhost‘;

 $C[‘DB_USER‘] = ‘root‘;
 
 $C[‘DB_PASS‘] = ‘123456‘;
 
 $C[‘DB_NAME‘] = ‘db_test‘;
 
 /**
  * 循环生成常量
  */
 foreach ($C as $name => $val) {
     define($name , $val);
 }

 /**
  * 用PDO链接数据库
  */
 $dbo = new PDO("mysql:host=" . DB_HOST . ";dbname=" . DB_NAME . "","" . DB_USER . "","" . DB_PASS . "") or die("数据库链接失败"); 

 /**
  * 试着写一个链接数据库的例子
  */
 
try{
	
 $rs = $dbo -> prepare("select * from `test`");
 
 $rs->execute();
 
 $results = $rs->FETCHALL(PDO::FETCH_ASSOC);
 
 $dbo = null;
 
 print_r($results);
}
catch( Exception $e)
{
	print $e->getMessage();
	exit;
}

/*End of file DB.class.php*/