PHP实现的XML操作类【XML Library】


            本文实例讲述了PHP实现的XML操作类。分享给大家供大家参考，具体如下：

这是一个接口程序，需要大量分析解析XML，PHP的xml_parse_into_struct()函数不能直接生成便于使用的数组，而SimpleXML扩展在PHP5中才支持，于是逛逛搜索引擎，在老外的网站上找到了一个不错的PHP XML操作类。

一、用法举例：

1、将XML文件解释成便于使用的数组：





<?php

include('xml.php'); //引用PHP XML操作类

$xml = file_get_contents('data.xml'); //读取XML文件

//$xml = file_get_contents("php://input"); //读取POST过来的输入流

$data=XML_unserialize($xml);

echo '<pre>';

print_r($data);

echo '</pre>';

?>







data.xml文件：





<?xml version="1.0" encoding="GBK"?>

<video>

<upload>

<videoid>998</videoid>

<name><![CDATA[回忆未来]]></name>

<memo><![CDATA[def]]></memo>

<up_userid>11317</up_userid>

</upload>

</video>







利用该XML操作类生成的对应数组（汉字编码：UTF-8）：





Array

(

 [video] => Array

  (

   [upload] => Array

    (

     [videoid] => 998

     [name] => 回忆未来

     [memo] => def

     [up_userid] => 11317

    )

  )

)







2、将数组转换成XML文件：





<?php

include('xml.php');//引用PHP XML操作类

$xml = XML_serialize($data);

?>







二、PHP XML操作类源代码：





<?php

###################################################################################

# XML_unserialize: takes raw XML as a parameter (a string)

# and returns an equivalent PHP data structure

###################################################################################

function & XML_unserialize(&$xml){

 $xml_parser = &new XML();

 $data = &$xml_parser->parse($xml);

 $xml_parser->destruct();

 return $data;

}

###################################################################################

# XML_serialize: serializes any PHP data structure into XML

# Takes one parameter: the data to serialize. Must be an array.

###################################################################################

function & XML_serialize(&$data, $level = 0, $prior_key = NULL){

 if($level == 0){ ob_start(); echo '<?xml version="1.0" ?>',"\n"; }

 while(list($key, $value) = each($data))

  if(!strpos($key, ' attr')) #if it's not an attribute

   #we don't treat attributes by themselves, so for an emptyempty element

   # that has attributes you still need to set the element to NULL

   if(is_array($value) and array_key_exists(0, $value)){

    XML_serialize($value, $level, $key);

   }else{

    $tag = $prior_key ? $prior_key : $key;

    echo str_repeat("\t", $level),'<',$tag;

    if(array_key_exists("$key attr", $data)){ #if there's an attribute for this element

     while(list($attr_name, $attr_value) = each($data["$key attr"]))

      echo ' ',$attr_name,'="',htmlspecialchars($attr_value),'"';

     reset($data["$key attr"]);

    }

    if(is_null($value)) echo " />\n";

    elseif(!is_array($value)) echo '>',htmlspecialchars($value),"</$tag>\n";

    else echo ">\n",XML_serialize($value, $level+1),str_repeat("\t", $level),"</$tag>\n";

   }

 reset($data);

 if($level == 0){ $str = &ob_get_contents(); ob_end_clean(); return $str; }

}

###################################################################################

# XML class: utility class to be used with PHP's XML handling functions

###################################################################################

class XML{

 var $parser; #a reference to the XML parser

 var $document; #the entire XML structure built up so far

 var $parent; #a pointer to the current parent - the parent will be an array

 var $stack; #a stack of the most recent parent at each nesting level

 var $last_opened_tag; #keeps track of the last tag opened.

 function XML(){

   $this->parser = &xml_parser_create();

  xml_parser_set_option(&$this->parser, XML_OPTION_CASE_FOLDING, false);

  xml_set_object(&$this->parser, &$this);

  xml_set_element_handler(&$this->parser, 'open','close');

  xml_set_character_data_handler(&$this->parser, 'data');

 }

 function destruct(){ xml_parser_free(&$this->parser); }

 function & parse(&$data){

  $this->document = array();

  $this->stack = array();

  $this->parent = &$this->document;

  return xml_parse(&$this->parser, &$data, true) ? $this->document : NULL;

 }

 function open(&$parser, $tag, $attributes){

  $this->data = ''; #stores temporary cdata

  $this->last_opened_tag = $tag;

  if(is_array($this->parent) and array_key_exists($tag,$this->parent)){ #if you've seen this tag before

   if(is_array($this->parent[$tag]) and array_key_exists(0,$this->parent[$tag])){ #if the keys are numeric

    #this is the third or later instance of $tag we've come across

    $key = count_numeric_items($this->parent[$tag]);

   }else{

    #this is the second instance of $tag that we've seen. shift around

    if(array_key_exists("$tag attr",$this->parent)){

     $arr = array('0 attr'=>&$this->parent["$tag attr"], &$this->parent[$tag]);

     unset($this->parent["$tag attr"]);

    }else{

     $arr = array(&$this->parent[$tag]);

    }

    $this->parent[$tag] = &$arr;

    $key = 1;

   }

   $this->parent = &$this->parent[$tag];

  }else{

   $key = $tag;

  }

  if($attributes) $this->parent["$key attr"] = $attributes;

  $this->parent = &$this->parent[$key];

  $this->stack[] = &$this->parent;

 }

 function data(&$parser, $data){

  if($this->last_opened_tag != NULL) #you don't need to store whitespace in between tags

   $this->data .= $data;

 }

 function close(&$parser, $tag){

  if($this->last_opened_tag == $tag){

   $this->parent = $this->data;

   $this->last_opened_tag = NULL;

  }

  array_pop($this->stack);

  if($this->stack) $this->parent = &$this->stack[count($this->stack)-1];

 }

}

function count_numeric_items(&$array){

 return is_array($array) ? count(array_filter(array_keys($array), 'is_numeric')) : 0;

}

?>







PS：这里再为大家提供几款关于xml操作的在线工具供大家参考使用：

在线XML/JSON互相转换工具：

http://tools.zwyuanma.com/code/xmljson

在线格式化XML/在线压缩XML：

http://tools.zwyuanma.com/code/xmlformat

XML在线压缩/格式化工具：

http://tools.zwyuanma.com/code/xml_format_compress

XML代码在线格式化美化工具：

http://tools.zwyuanma.com/code/xmlcodeformat

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希望本文所述对大家PHP程序设计有所帮助。