php生成xml文件的四种方法

<?xml version="1.0" encoding="utf-8"?>
<article>
    <item>
        <title size="1">title1</title>
        <content>content1</content>
        <pubdate>2009-10-11</pubdate>
    </item>
    <item>
        <title size="1">title2</title>
        <content>content2</content>
        <pubdate>2009-11-11</pubdate>
    </item>
</article>

<?PHP
$data_array = array(
    array(
    'title' => 'title1',
    'content' => 'content1',
        'pubdate' => '2009-10-11',
    ),
    array(
    'title' => 'title2',
    'content' => 'content2',
    'pubdate' => '2009-11-11',
    )
);
$title_size = 1;

$xml = "<?xml version="1.0" encoding="utf-8"?>n";
$xml .= "<article>n";

foreach ($data_array as $data) {
$xml .= create_item($data['title'], $title_size, $data['content'], $data['pubdate']);
}

$xml .= "</article>n";
echo $xml;

//创建XML单项
function create_item($title_data, $title_size, $content_data, $pubdate_data)
{
    $item = "<item>n";
    $item .= "<title size="" . $title_size . "">" . $title_data . "</title>n";
    $item .= "<content>" . $content_data . "</content>n";
    $item .= " <pubdate>" . $pubdate_data . "</pubdate>n";
    $item .= "</item>n";

    return $item;
}
?>

<?php
$data_array = array(
    array(
    'title' => 'title1',
    'content' => 'content1',
        'pubdate' => '2009-10-11',
    ),
    array(
    'title' => 'title2',
    'content' => 'content2',
    'pubdate' => '2009-11-11',
    )
);

//  属性数组
$attribute_array = array(
    'title' => array(
    'size' => 1
    )
);

//  创建一个XML文档并设置XML版本和编码。。
$dom=new DomDocument('1.0', 'utf-8');

//  创建根节点
$article = $dom->createElement('article');
$dom->appendchild($article);

foreach ($data_array as $data) {
    $item = $dom->createElement('item');
    $article->appendchild($item);
    create_item($dom, $item, $data, $attribute_array);
}
echo $dom->saveXML();

function create_item($dom, $item, $data, $attribute) {
    if (is_array($data)) {
        foreach ($data as $key => $val) {
            //  创建元素
            $$key = $dom->createElement($key);
            $item->appendchild($$key);

            //  创建元素值
            $text = $dom->createTextNode($val);
            $$key->appendchild($text);

            if (isset($attribute[$key])) {
            //  如果此字段存在相关属性需要设置
                foreach ($attribute[$key] as $akey => $row) {
                    //  创建属性节点
                    $$akey = $dom->createAttribute($akey);
                    $$key->appendchild($$akey);

                    // 创建属性值节点
                    $aval = $dom->createTextNode($row);
                    $$akey->appendChild($aval);
                }
            }   //  end if
        }
    }   //  end if
}   //  end function
?>