php写的 xml操作类

XML作为轻量级的数据库还是挺好用的，当XML不超过2M大小的时候读取速度还是很快的。以下提供我自己写的XML操作类。

如果用户想循环利用XML作为数据库的话，只要记录节点总数，当到达一个饱和数量时，又重新初始化XML即可。

<?php

class requirelog

{

    protected static $requirelog;



    //get ready for xml,if xml is not found ,create xml

    static function _initializeLog()

    {

       if(file_exists('requirelog.xml'))

       {



           self::$requirelog = DOMDocument::load('requirelog.xml');

       }

       else

       {

           self::$requirelog = new DOMDocument('1.0', 'iso-8859-1');

           self::$requirelog->loadXML('<?xml version="1.0" encoding="UTF-8"?><contents></contents>');

           self::$requirelog->save('requirelog.xml');

       }

    }







    //获取finish字段全部为0的所有节点

    public static function get_entrys()

    {

            self::_initializeLog();

            $entrys = self::$requirelog->getElementsByTagName('entry');

            $entry_arrays = array();

            foreach($entrys as $entry)

            {

                if($entry->getElementsByTagName('finish')->item(0)->nodeValue == 0)

                {

                    $entry_array = array();

                    $entry_array['id'] = $entry->getElementsByTagName('id')->item(0)->nodeValue;

                    $entry_array['time'] = $entry->getElementsByTagName('time')->item(0)->nodeValue;

                    $entry_array['operator'] = $entry->getElementsByTagName('operator')->item(0)->nodeValue;

                    $entry_array['byoperator'] = $entry->getElementsByTagName('byoperator')->item(0)->nodeValue;

                    $entry_array['parameters1'] = $entry->getElementsByTagName('parameters1')->item(0)->nodeValue;

                    $entry_array['parameters2'] = $entry->getElementsByTagName('parameters2')->item(0)->nodeValue;

                    $entry_array['parameters3'] = $entry->getElementsByTagName('parameters3')->item(0)->nodeValue;



                    $entry_array['type'] = $entry->getElementsByTagName('type')->item(0)->nodeValue;

                    $entry_array['module'] = $entry->getElementsByTagName('module')->item(0)->nodeValue;

                    $entry_array['finish'] = $entry->getElementsByTagName('finish')->item(0)->nodeValue;

                    $entry_arrays[] = $entry_array;

                }

            }

            return  $entry_arrays;

    }



    

    //获取所有的节点

    public static function get_count_entrys()

    {

            self::_initializeLog();

            $entrys = self::$requirelog->getElementsByTagName('entry');

            $entry_arrays = array();

            foreach($entrys as $entry)

            {



                $entry_array = array();

                $entry_array['id'] = $entry->getElementsByTagName('id')->item(0)->nodeValue;

                $entry_array['time'] = $entry->getElementsByTagName('time')->item(0)->nodeValue;

                $entry_array['operator'] = $entry->getElementsByTagName('operator')->item(0)->nodeValue;

                $entry_array['byoperator'] = $entry->getElementsByTagName('byoperator')->item(0)->nodeValue;

                $entry_array['parameters1'] = $entry->getElementsByTagName('parameters1')->item(0)->nodeValue;

                $entry_array['parameters2'] = $entry->getElementsByTagName('parameters2')->item(0)->nodeValue;

                $entry_array['parameters3'] = $entry->getElementsByTagName('parameters3')->item(0)->nodeValue;



                $entry_array['type'] = $entry->getElementsByTagName('type')->item(0)->nodeValue;

                $entry_array['module'] = $entry->getElementsByTagName('module')->item(0)->nodeValue;

                $entry_array['finish'] = $entry->getElementsByTagName('finish')->item(0)->nodeValue;

                $entry_arrays[] = $entry_array;



            }

            return  $entry_arrays;

    }



    //根据ID获取节点

    public static function get_entry($id)

    {

        self::_initializeLog();

        $count=count(self::get_count_entrys());

        if($count > 0)

        {

            $entrys = self::$requirelog->getElementsByTagName('entry');

            foreach($entrys as $entry)

            {

                if ($id == $entry->getElementsByTagName('id')->item(0)->nodeValue)

                {

                    $entry_array = array();

                    $entry_array['id'] = $entry->getElementsByTagName('id')->item(0)->nodeValue;

                    $entry_array['time'] = $entry->getElementsByTagName('time')->item(0)->nodeValue;

                    $entry_array['operator'] = $entry->getElementsByTagName('operator')->item(0)->nodeValue;

                    $entry_array['byoperator'] = $entry->getElementsByTagName('byoperator')->item(0)->nodeValue;

                    $entry_array['parameters1'] = $entry->getElementsByTagName('parameters1')->item(0)->nodeValue;

                    $entry_array['parameters2'] = $entry->getElementsByTagName('parameters2')->item(0)->nodeValue;

                    $entry_array['parameters3'] = $entry->getElementsByTagName('parameters3')->item(0)->nodeValue;



                    $entry_array['type'] = $entry->getElementsByTagName('type')->item(0)->nodeValue;

                    $entry_array['module'] = $entry->getElementsByTagName('module')->item(0)->nodeValue;

                    $entry_array['finish'] = $entry->getElementsByTagName('finish')->item(0)->nodeValue;

                    return $entry_array;

                }

            }

        }

        else

            return null;

    }



    //执行完用户请求，更改finsh字段

    public static function do_finsh($id)

    {

        self::_initializeLog();

        $entrys = self::$requirelog->getElementsByTagName('entry');

        $entry_arrays = array();

        foreach($entrys as $entry)

        {

            if($entry->getElementsByTagName('id')->item(0)->nodeValue == $id)

            {

                $entry->getElementsByTagName('finish')->item(0)->nodeValue = 1;

            }

        }



        self::$requirelog->save('requirelog.xml');

    }





    //增加新节点,$operator为操作者，$byoperator是被操作对象，$parameters1,2,3为可扩展的参数，$type为类型，$module为影响的模块

   static function add_entry($operator,$byoperator,$parameters1,$parameters2,$parameters3,$type,$module)

    {

        //$contents = self::$restlog->getElementsByTagName('contents');



        self::_initializeLog();

        $count=count(self::get_count_entrys());



        $entry = self::$requirelog->createElement('entry');



        $id = self::$requirelog->createElement('id');

        $idvalue = self::$requirelog->createTextNode($count+1);

        $id->appendChild($idvalue);



        $time = self::$requirelog->createElement('time');

        $timevalue = self::$requirelog->createTextNode(date("Y-m-d H:i:s",time()));

        $time->appendChild($timevalue);



        $op = self::$requirelog->createElement('operator');

        $opvalue = self::$requirelog->createTextNode($operator);

        $op->appendChild($opvalue);



        $bop = self::$requirelog->createElement('byoperator');

        $bopvalue = self::$requirelog->createTextNode($byoperator);

        $bop->appendChild($bopvalue);



        $ps1 = self::$requirelog->createElement('parameters1');

        $ps1value = self::$requirelog->createTextNode($parameters1);

        $ps1->appendChild($ps1value);



        $ps2 = self::$requirelog->createElement('parameters2');

        $ps2value = self::$requirelog->createTextNode($parameters2);

        $ps2->appendChild($ps2value);



        $ps3 = self::$requirelog->createElement('parameters3');

        $ps3value = self::$requirelog->createTextNode($parameters3);

        $ps3->appendChild($ps3value);





        $tp = self::$requirelog->createElement('type');

        $tpvalue = self::$requirelog->createTextNode($type);

        $tp->appendChild($tpvalue);



        $md = self::$requirelog->createElement('module');

        $mdvalue = self::$requirelog->createTextNode($module);

        $md->appendChild($mdvalue);



        $fi = self::$requirelog->createElement('finish');

        $fivalue = self::$requirelog->createTextNode(0);

        $fi->appendChild($fivalue);





        $entry->appendChild($id);

        $entry->appendChild($time);

        $entry->appendChild($op);

        $entry->appendChild($bop);

        $entry->appendChild($ps1);

        $entry->appendChild($ps2);

        $entry->appendChild($ps3);

        $entry->appendChild($tp);

        $entry->appendChild($md);

        $entry->appendChild($fi);





        self::$requirelog->documentElement->appendChild($entry);

        self::$requirelog->save('requirelog.xml');



        return 1;



    }



}



?>

requirelog.xml的格式如下：

<?xml version="1.0" encoding="UTF-8"?>
<contents>
   <entry>
      <id>1</id>
      <time>2009-11-21 16:56:33</time>
      <operator>peng.zhou</operator>
      <byoperator>zxcxzcxzczxcxz</byoperator>
      <parameters1>cxzcxzc</parameters1>
      <parameters2/>
      <parameters3/>
      <type>add_group</type>
      <module>cn_group</module>
      <finish>1</finish>
   </entry>
   <entry>
      <id>2</id>
      <time>2009-11-21 16:56:53</time>
      <operator>peng.zhou</operator>
      <byoperator>sales</byoperator>
      <parameters1/>
      <parameters2/>
      <parameters3/>
      <type>add_member</type>
      <module>mail_group</module>
      <finish>1</finish>
   </entry>
</contents>