PHP基于MySQL数据库实现对象持久层的方法

本文实例讲述了php基于mysql数据库实现对象持久层的方法。分享给大家供大家参考。具体如下：

心血来潮，做了一下php的对象到数据库的简单持久层。

不常用php，对php也不熟，关于php反射的大部分内容都是现学的。

目前功能比较弱，只是完成一些简单的工作，对象之间的关系还没法映射，并且对象的成员只能支持string或者integer两种类型的。

成员变量的值也没有转义一下。。。

下面就贴一下代码：

首先是数据库的相关定义，该文件定义了数据库的连接属性：

<?php 
/* 
 * filename: config.php 
 * created on 2012-9-29 
 * created by robintang 
 * to change the template for this generated file go to 
 * window - preferences - phpeclipse - php - code templates 
 */ 
  // about database 
  define('dbhost', 'localhost'); // 数据库服务器 
  define('dbname', 'db_wdid'); // 数据库名称 
  define('dbuser', 'root'); // 登陆用户名 
  define('dbpswd', 'trb'); // 登录密码 
?> 

下面是数据库访问的简单封装：

<?php 
/* 
 * filename: database.php 
 * created on 2012-9-29 
 * created by robintang 
 * to change the template for this generated file go to 
 * window - preferences - phpeclipse - php - code templates 
 */ 
  include_once("config.php"); 
  $debug = false; 
  $g_out = false; 
  function out($s){ 
    global $g_out; 
    $g_out .= $s; 
    $g_out .= "\r\n"; 
  } 
  function db_openconnect(){ 
    $con = mysql_connect(dbhost, dbuser, dbpswd); 
     
    if(!mysql_set_charset("utf8", $con)){ 
      out("set mysql encoding fail"); 
    } 
    if (!$con){ 
      out('could not connect: ' . mysql_error()); 
    } 
    else{ 
      if(!mysql_select_db(dbname, $con)){ 
        $dbn = dbname; 
        out("could select database '$dbn' : " . mysql_error());
      } 
      $sql = "set time_zone = '+8:00';"; 
      if(!db_onlyquery($sql, $con)){ 
        out("select timezone fail!" . mysql_error()); 
      } 
    } 
    return $con; 
  } 
  function db_colseconnect($con){ 
    mysql_close($con); 
  } 
  function db_onlyquery($sql, $con){ 
    $r = mysql_query($sql, $con); 
    if(!$r){ 
      out("query '$sql' :fail"); 
      return false; 
    } 
    else{ 
      return $r; 
    } 
  } 
  function db_query($sql){ 
    $con = db_openconnect(); 
    $r = db_onlyquery($sql, $con); 
    $res = false; 
    if($r){ 
      $res = true; 
    } 
    db_colseconnect($con); 
    return $r; 
  } 
  function db_query_effect_rows($sql){ 
    $con = db_openconnect(); 
    $r = db_onlyquery($sql, $con); 
    $res = false; 
    if($r){ 
      $res = mysql_affected_rows($con); 
      if($res==0){ 
        $res = -1; 
      } 
    } 
    else{ 
      $res = false; 
    } 
    db_colseconnect($con); 
    return $res; 
  } 
  function db_getresult($sql){ 
    $con = db_openconnect(); 
    $r = db_onlyquery($sql, $con); 
    $res = false; 
    if($r && $arr = mysql_fetch_row($r)){ 
      $res = $arr[0]; 
    } 
    db_colseconnect($con); 
    return $res; 
  } 
  function db_getarray($sql){ 
    $con = db_openconnect(); 
    $r = db_onlyquery($sql, $con); 
    $ret = false; 
    if($r){ 
      $row = false; 
      $len = 0; 
      $ret = array(); 
      $i = 0; 
      while($arr = mysql_fetch_row($r)){ 
        if($row == false || $len==0){ 
          $row = array(); 
          $len = count($arr); 
          for($i=0;$i<$len;++$i){ 
            $key = mysql_field_name($r, $i); 
            array_push($row, $key); 
          } 
        } 
        $itm = array(); 
        for($i=0;$i<$len;++$i){ 
          $itm[$row[$i]]=$arr[$i]; 
        } 
        array_push($ret, $itm); 
      } 
    } 
    db_colseconnect($con); 
    return $ret; 
  } 
?> 

其实上面的两个文件都是之前写好的，持久层的东西是下面的：

<?php 
/* 
 * filename: sinorm.php 
 * created on 2012-11-4 
 * created by robintang 
 * to change the template for this generated file go to 
 * window - preferences - phpeclipse - php - code templates 
 */ 
  include_once("database.php"); 
   
  function sinorm_execsql($sql) { 
    return db_query($sql); 
  } 
  function sinorm_execarray($sql) { 
    return db_getarray($sql); 
  } 
  function sinorm_execresult($sql){ 
    return db_getresult($sql); 
  } 
  function sinorm_getclasspropertys($class) { 
    $r = new reflectionclass($class); 
    if (!$r->hasproperty('tablename')) { 
      throw new exception("class '$class' has no [tablename] property"); 
    } 
    $table = $r->getstaticpropertyvalue('tablename'); 
    if (!$r->hasproperty('id')) { 
      throw new exception("class '$class' has no [id] property");
    } 
    $mpts = array (); 
    $pts = $r->getproperties(reflectionproperty :: is_public); 
    foreach ($pts as $pt) { 
      if (!$pt->isstatic()) { 
        array_push($mpts, $pt); 
      } 
    } 
    return array ( 
      $table, 
      $mpts 
    ); 
  } 
  function sinorm_getpropertystring($pts, $class, $obj = false, $noid = false) { 
    if (is_null($pts)) { 
      list ($tb, $pts) = sinorm_getclasspropertys($class); 
    } 
    $s = false; 
    $v = false; 
    $l = false; 
    foreach ($pts as $pt) { 
      $name = $pt->name; 
      if ($noid == false || $name != 'id') { 
        if ($l) { 
          $s = $s . ','; 
        } 
        $s = $s . $name; 
   
        if ($obj) { 
          if ($l) { 
            $v = $v . ','; 
          } 
          $val = $pt->getvalue($obj); 
          if (is_null($val)) 
            $v = $v . 'null'; 
          if (is_string($val)) 
            $v = $v . "'$val'"; 
          else 
            $v = $v . $val; 
        } 
        $l = true; 
      } 
    } 
    return array ( 
      $s, 
      $v 
    ); 
  } 
  function sinorm_gettablename($class){ 
    $r = new reflectionclass($class); 
    if (!$r->hasproperty('tablename')) { 
      throw new exception("class '$class' has no [tablename] property"); 
    } 
    $table = $r->getstaticpropertyvalue('tablename'); 
    if (!$r->hasproperty('id')) { 
      throw new exception("class '$class' has no [id] property"); 
    } 
    return $table; 
  } 
  function sinorm_resetorm($class) { 
    list ($tb, $pts) = sinorm_getclasspropertys($class); 
    $sql = "create table `$tb` (`id` int not null auto_increment"; 
    $r = new reflectionclass($class); 
    $obj = $r->newinstance(); 
    foreach ($pts as $pt) { 
      $val = $pt->getvalue($obj); 
      $name = $pt->name; 
      if ($name != 'id') { 
        $sql = $sql . ','; 
      } else { 
        continue; 
      } 
      if (is_null($val)) 
        throw new exception($class . '->' . "name must have a default value"); 
      if (is_string($val)) 
        $sql = $sql . "`$name` text null"; 
      else 
        $sql = $sql . "`$name` int null"; 
    } 
    $sql = $sql . ",primary key (`id`));"; 
    $dsql = "drop table if exists `$tb`;"; 
    return sinorm_execsql($dsql) && sinorm_execsql($sql); 
  } 
  function sinorm_saveobject($obj) { 
    $class = get_class($obj); 
    list ($tb, $pts) = sinorm_getclasspropertys($class); 
    list ($names, $vals) = sinorm_getpropertystring($pts, $class, $obj, true); 
    $sql = "insert into `$tb`($names) values($vals)"; 
    if(sinorm_execsql($sql)){ 
      $q = "select `id` from `$tb` order by `id` desc limit 1;"; 
      $id = sinorm_execresult($q); 
      if($id){ 
        $obj->id = $id; 
      } 
    } 
    return false; 
  } 
  function sinorm_getobjects($class) { 
    list ($tb, $pts) = sinorm_getclasspropertys($class); 
    $sql = "select * from `$tb`;"; 
    $ary = sinorm_execarray($sql); 
    $res = false; 
    if (is_array($ary)) { 
      $res = array (); 
      $ref = new reflectionclass($class); 
      foreach ($ary as $a) { 
        $obj = $ref->newinstance(); 
        foreach ($pts as $pt) { 
          $name = $pt->name; 
          $olv = $pt->getvalue($obj); 
          $val = $a[$name]; 
          if (is_string($olv)) 
            $pt->setvalue($obj, $val); 
          else 
            $pt->setvalue($obj, intval($val)); 
        } 
        array_push($res, $obj); 
      } 
    } else { 
      echo 'no'; 
    } 
    return $res; 
  } 
  function sinorm_getobject($class, $id) { 
    list ($tb, $pts) = sinorm_getclasspropertys($class); 
    $sql = "select * from `$tb` where `id`=$id;"; 
    $ary = sinorm_execarray($sql); 
    $res = null; 
    if (is_array($ary) && count($ary) > 0) { 
      $res = array (); 
      $ref = new reflectionclass($class); 
      $a = $ary[0]; 
      $obj = $ref->newinstance(); 
      foreach ($pts as $pt) { 
        $name = $pt->name; 
        $olv = $pt->getvalue($obj); 
        $val = $a[$name]; 
        if (is_string($olv)) 
          $pt->setvalue($obj, $val); 
        else 
          $pt->setvalue($obj, intval($val)); 
      } 
      return $obj; 
    } 
    return null; 
  } 
  function sinorm_update($obj) { 
    $class = get_class($obj); 
    list ($tb, $pts) = sinorm_getclasspropertys($class); 
    $sql = "update `$tb` set "; 
    $l = false; 
    foreach ($pts as $pt) { 
      $name = $pt->name; 
      $val = $pt->getvalue($obj); 
      if ($name == 'id') 
        continue; 
      if ($l) 
        $sql = $sql . ','; 
      if (is_string($val)) 
        $sql = $sql . "$name='$val'"; 
      else 
        $sql = $sql . "$name=$val"; 
      $l = true; 
    } 
    $sql = $sql . " where `id`=$obj->id;"; 
    return sinorm_execsql($sql); 
  } 
  function sinorm_saveorupdate($obj) { 
    if (sinorm_getobject(get_class($obj), $obj->id) == null) { 
      sinorm_saveobject($obj); 
    } else { 
      sinorm_update($obj); 
    } 
  } 
  function sinorm_deleteobject($obj){ 
    $class = get_class($obj); 
    $tb = sinorm_gettablename($class); 
    $sql = "delete from `$tb` where `id`=$obj->id;"; 
    return sinorm_execsql($sql); 
  } 
  function sinorm_deleteall($class){ 
    $tb = sinorm_gettablename($class); 
    $sql = "delete from `$tb`;"; 
    return sinorm_execsql($sql); 
  } 
?> 

下面是使用的例子：

<?php 
/* 
 * filename: demo.php 
 * created on 2012-11-4 
 * created by robintang 
 * to change the template for this generated file go to 
 * window - preferences - phpeclipse - php - code templates 
 */ 
  include_once("sinorm.php"); 
  // 下面是一个持久对象的类的定义 
  // 每个持久对象类都必须有一个叫做$tablename静态成员，它表示数据库中存储对象的表名 
  // 类的每个成员都必须初始化，也就是必须给它一个初始值 
  // 成员变量只能为字符串或者整型，而且请定义成public的，只有public的成员变量会被映射 
  class user{ 
    public static $tablename = 't_user';  // 静态变量，对象的表名，必须的 
    public $id = 0; // 对象id,对应表中的主键，必须的，而且必须初始化为0 
     
    public $name = ''; // 姓名，必须初始化 
    public $age = 0; // 年龄，必须初始化 
    public $email = ''; // 必须初始化  
  } 
   
  // 注意：下面的语句一定要在定义好类之后运行一下，修改了类也需要运行一下，它完成创建表的工作 
  // sinorm_resetorm('user'); // 这一句只是一开始执行一次，执行之后就会自动在数据库中建立user对应的表 
   
  $user1 = new user();  // 创建一个对象 
  $user1->name = 'trb'; 
  $user1->age = 22; 
  $user1->email = '[e-mail]'; 
  sinorm_saveobject($user1); // 把对象保存到数据库中 
   
  // 保存之后会自动给id的 
  $id = $user1->id; 
  echo $id . '<br/>'; 
    
  $user2 = sinorm_getobject('user', $id); // 通过id从数据库创建一个对象 
  echo $user2->name . '<br/>'; 
   
  $user1->name = 'trb'; // 改变一下 
  sinorm_update($user1); // 更新到数据库 
   
  $user3 = sinorm_getobject('user', $id); // 重新读出 
  echo $user3->name . '<br/>'; 
?> 

希望本文所述对大家的php程序设计有所帮助。