php读取xml文件的三种实现方法
文章介绍了三种方式来读取xml文件分别是new DOMDocument(),正则解析xml,用parser函数来读取xml数据,这些方法都是可行的,但第一种和最后一种要好一些.
new DOMDocument()实例代码如下:
<?php
$doc = new DOMDocument();
$doc->load('books.xml');
$books = $doc->getElementsByTagName("book");
foreach ($books as $book) {
$authors = $book->getElementsByTagName("author");
$author = $authors->item(0)->nodeValue;
$publishers = $book->getElementsByTagName("publisher");
$publisher = $publishers->item(0)->nodeValue;
$titles = $book->getElementsByTagName("title");
$title = $titles->item(0)->nodeValue;
echo "$title - $author - $publisher/n";
}
?>正则解析,代码如下:
<?php
$xml = "";
$f = fopen('books.xml', 'r');
while ($data = fread($f, 4096)) {
$xml.= $data;
}
fclose($f);
preg_match_all("//<book/>(.*?)/<//book/>/s", $xml, $bookblocks);
foreach ($bookblocks[1] as $block) {
preg_match_all("//<author/>(.*?)/<//author/>/", $block, $author);
preg_match_all("//<title/>(.*?)/<//title/>/", $block, $title);
preg_match_all("//<publisher/>(.*?)/<//publisher/>/", $block, $publisher);
echo ($title[1][0] . " - " . $author[1][0] . " - " . $publisher[1][0] . "/n");
}
?>books.xml文件如下:
<books> <book> <author>Jack Herrington</author> <title>PHP Hacks</title> <publisher>O'Reilly</publisher> </book> <book> <author>Jack Herrington</author> <title>Podcasting Hacks</title> <publisher>O'Reilly</publisher> </book> </books>
下面就给大家举一个小小的例子用parser函数来读取xml数据,代码如下:
<?php
$parser = xml_parser_create(); //创建一个parser编辑器
xml_set_element_handler($parser, "startElement", "endElement"); //设立标签触发时的相应函数 这里分别为startElement和endElenment
xml_set_character_data_handler($parser, "characterData"); //设立数据读取时的相应函数
$xml_file = "1.xml"; //指定所要读取的xml文件,可以是url
$filehandler = fopen($xml_file, "r"); //打开文件
while ($data = fread($filehandler, 4096)) {
xml_parse($parser, $data, feof($filehandler));
} //每次取出4096个字节进行处理
fclose($filehandler);
xml_parser_free($parser); //关闭和释放parser解析器
$name = false;
$position = false;
function startElement($parser_instance, $element_name, $attrs) //起始标签事件的函数
{
global $name, $position;
if ($element_name == "NAME") {
$name = true;
$position = false;
echo "名字:";
}
if ($element_name == "POSITION") {
$name = false;
$position = true;
echo "职位:";
}
}
function characterData($parser_instance, $xml_data) //读取数据时的函数
{
global $name, $position;
if ($position) echo $xml_data . "<br>";
if ($name) echo $xml_data . "<br>";
}
function endElement($parser_instance, $element_name) //结束标签事件的函数
{
global $name, $position;
$name = false;
$position = false;
}
?>xml文件代码如下:
<?xml version="1.0" <employees> <employee> <name>张三</name> <position age="45">经理</position> </employee> <employees> <employee> <name>李四</name> <position age="45">助理</position> </employee> </employees>
parser是php内置的一个用来处理xml的解析器,它的工作由三个事件组成:起始标签、 读取数据、结束标签.
也就是说在对xml进行处理的时候每当遇到起始标签、数据和结束标签的时候函数会做相应的动作来完成对xml数据的转换.
教程链接:http://www.phprm.com/develop/fs4545.html
随意转载~但请保留教程地址★