生成XML的四种方式

1. 使用纯粹的PHP代码生成字符串,并把这个字符串写入一个以XML为后缀的文件

   function create_item($titleData, $titleSize, $contentData, $pubdateData)
   {
       $item = "<item>\n";
       $item .= "<title size=\"" . $titleSize . "\">" . $titleData . "</title>\n";
       $item .= "<content>" . $contentData . "</content>\n";
       $item .= "<pubdate>" . $pubdateData . "</pubdate>\n";
       $item .= "</item>\n";
       return $item;
   }
   
   $dataArray = [
       [
           'title' => 'title1',
           'content' => 'content1',
           'pubdate' => '2009-10-11'
       ],
       [
           'title' => 'title2',
           'content' => 'content2',
           'pubdate' => '2009-11-11'
       ]
   ];
   $titleSize = 1;
   $xml = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n";
   $xml .= "<article>\n";
   foreach ($dataArray as $data) {
       $xml .= create_item($data['title'], $titleSize, $data['content'], $data['pubdate']);
   }
   $xml .= "</article>\n";
   echo $xml;

1. 使用DomDocument生成XML文件,创建节点使用createElement方法,创建文本内容使用createTextNode方法,添加子节点使用appendChild方法,创建属性使用createAttribute方法

   // $$ 可变变量,例：$one = 'hello'; $hello = 'world'; echo $one . ' ' . $$one; 结果为： hello world
   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);
                   }
               }
           }
       }
   }
   
   $dataArray = [
       [
           'title' => 'title1',
           'content' => 'content1',
           'pubdate' => '2009-10-11'
       ],
       [
           'title' => 'title2',
           'content' => 'content2',
           'pubdate' => '2009-11-11'
       ]
   ];
   // 属性数组
   $attributeArray = ['title' => ['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 ($dataArray as $data) {
       $item = $dom->createElement('item');
       $article->appendchild($item);
       create_item($dom, $item, $data, $attributeArray);
   }
   echo $dom->saveXML();

2. 使用XMLWriter类创建XML文件,此方法在PHP 5.1.2后有效.另外,它可以输出多种编码的XML,但是输入只能是utf-8

   $dataArray = [
       [
           'title' => 'title1',
           'content' => 'content1',
           'pubdate' => '2009-10-11'
       ],
       [
           'title' => 'title2',
           'content' => 'content2',
           'pubdate' => '2009-11-11'
       ]
   ];
   // 属性数组
   $attributeArray = ['title' => ['size' => 1]];
   $xml = new XMLWriter();
   $xml->openUri("php://output");
   // 输出方式, 也可以设置为某个xml文件地址, 直接输出成文件
   $xml->setIndentString('  ');
   $xml->setIndent(true);
   $xml->startDocument('1.0', 'utf-8');
   // 开始创建文件, 根结点
   $xml->startElement('article');
   foreach ($dataArray as $data) {
       $xml->startElement('item');
       if (is_array($data)) {
           foreach ($data as $key => $row) {
               $xml->startElement($key);
               if (isset($attributeArray[$key]) && is_array($attributeArray[$key])) {
                   foreach ($attributeArray[$key] as $akey => $aval) {
                       // 设置属性值
                       $xml->writeAttribute($akey, $aval);
                   }
               }
   
               $xml->text($row);
               $xml->endElement();
           }
       }
       $xml->endElement();
   }
   $xml->endElement();
   $xml->endDocument();
   $xml->flush();

3. 使用SimpleXML创建XML文档

   $dataArray = [
       [
           'title' => 'title1',
           'content' => 'content1',
           'pubdate' => '2009-10-11'
       ],
       [
           'title' => 'title2',
           'content' => 'content2',
           'pubdate' => '2009-11-11'
       ]
   ];
   // 属性数组
   $attributeArray = ['title' => ['size' => 1]];
    
   // 第一种
   $string = <<<XML
   <?xml version="1.0" encoding="utf-8"?>
   <article>
   </article>
   XML;
   $xml = simplexml_load_string($string);
    
   // 第二种
   $xml = new SimpleXMLElement('<?xml version="1.0" encoding="utf-8"?><article></article>'); 
   foreach ($dataArray as $data) {
       $item = $xml->addChild('item');
       if (is_array($data)) {
           foreach ($data as $key => $row) {
               $node = $item->addChild($key, $row);
               if (isset($attributeArray[$key]) && is_array($attributeArray[$key])) {
                   foreach ($attributeArray[$key] as $akey => $aval) {
                       // 设置属性值
                       $node->addAttribute($akey, $aval);
                   }
               }
           }
       }
   }
   echo $xml->asXML();