PHP读取XML 值 PHP读取XML 内容

Php读取XML第三种情况:

XML文件(cy.xml)如下:
<?xml version="1.0" encoding="gb2312"?>
<xml>
<main>
<list>1</list>
<list>2</list>
<list>3</list>
</main>
<main>
<list>4</list>
<list>5</list>
<list>6</list>
</main>
</xml>

Php文件(cy.php)如下(和第一次依然没有变化):
<?php
$xml = new DOMDocument();
$xml->load('cy.xml');
foreach($xml->getElementsByTagName_r('list') as $list)
{
$value = $list->firstChild->nodeValue;
echo $value."<br />";
}
?>

cy.php的输出结果:
1
2
3
4
5
6

===========

Php读取XML第四种情况,保持cy.xml不变,改变cy.php:

XML文件(cy.xml)如下:
<?xml version="1.0" encoding="gb2312"?>
<xml>
<main>
<list>1</list>
<list>2</list>
<list>3</list>
</main>
<main>
<list>4</list>
<list>5</list>
<list>6</list>
</main>
</xml>

Php文件(cy.php)如下:
<?php
$xml = new DOMDocument();
$xml->load('cy.xml');
$main = $xml->getElementsByTagName_r('main');
foreach( $main as $main)
{
$list = $main->getElementsByTagName_r( "list" );
foreach ( $list as $list )
{
$value = $list->firstChild->nodeValue;  Php读取XML第三种情况:

XML文件(cy.xml)如下:
<?xml version="1.0" encoding="gb2312"?>
<xml>
<main>
<list>1</list>
<list>2</list>
<list>3</list>
</main>
<main>
<list>4</list>
<list>5</list>
<list>6</list>
</main>
</xml>

Php文件(cy.php)如下(和第一次依然没有变化):
<?php
$xml = new DOMDocument();
$xml->load('cy.xml');
foreach($xml->getElementsByTagName_r('list') as $list)
{
$value = $list->firstChild->nodeValue;
echo $value."<br />";
}
?>

cy.php的输出结果:
1
2
3
4
5
6

===========

Php读取XML第四种情况,保持cy.xml不变,改变cy.php:

XML文件(cy.xml)如下:
<?xml version="1.0" encoding="gb2312"?>
<xml>
<main>
<list>1</list>
<list>2</list>
<list>3</list>
</main>
<main>
<list>4</list>
<list>5</list>
<list>6</list>
</main>
</xml>

Php文件(cy.php)如下:
<?php
$xml = new DOMDocument();
$xml->load('cy.xml');
$main = $xml->getElementsByTagName_r('main');
foreach( $main as $main)
{
$list = $main->getElementsByTagName_r( "list" );
foreach ( $list as $list )
{
$value = $list->firstChild->nodeValue;  
echo $value."<br />";
}
}
?>

cy.php输出结果:
1
2
3
4
5
6

为什么两次的cy.php不同,但输出结果是相同的?让我们来看下一个例子

==============

Php读取XML第五种情况,改变cy.xml,使cy.php保持第四种情况:

XML文件(cy.xml)如下:
<?xml version="1.0" encoding="gb2312"?>
<xml>

<main>
<list>1</list>
<list>2</list>
<list>3</list>
</main>
<main>
<list>4</list>
<list>5</list>
<list>6</list>
</main>
<m>
<list>7</list>
<list>8</list>
<list>9</list>
</m>

</xml>

Php文件(cy.php)和第四种情况相同:
<?php
$xml = new DOMDocument();
$xml->load('cy.xml');
$main = $xml->getElementsByTagName_r('main');
foreach( $main as $main)
{
$list = $main->getElementsByTagName_r( "list" );
foreach ( $list as $list )
{
$value = $list->firstChild->nodeValue;
echo $value."<br />";
}
}
?>

cy.php输出结果为:
1
2
3
4
5
6

为什么
<m>
<list>7</list>
<list>8</list>
<list>9</list>
</m>
中的7,8,9没有被读出来?
因为我们的cy.php只读取<main></main>标记中的内容.<m></m>标记中的内容是不会被读取的.
我们这里所提到的"标记",在XML里被称做"节点";
注:$xml->load('cy.xml');加载XML文件
$xml->loadXML('cy.xml');加载XML格式的字符串