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 = 'trbbadboy@qq.com';

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。