xml

由 xml_parser_create() 和 xml_parser_create_ns() 返回的 xml 资源引用了一个 XML 解析器实例，将被用在本扩展库提供的函数中。

XML 元素结构范例

第一个范例用缩进格式显示一个文档中起始元素的结构。

例子 1. 显示 XML 元素结构 <?php $file = "data.xml"; $depth = array(); function startElement($parser, $name, $attrs) {     global $depth;     for ($i = 0; $i < $depth[$parser]; $i++) {         echo "  ";     }     echo "$name\n";     $depth[$parser]++; } function endElement($parser, $name) {     global $depth;     $depth[$parser]--; } $xml_parser = xml_parser_create(); xml_set_element_handler($xml_parser, "startElement", "endElement"); if (!($fp = fopen($file, "r"))) {     die("could not open XML input"); } while ($data = fread($fp, 4096)) {     if (!xml_parse($xml_parser, $data, feof($fp))) {         die(sprintf("XML error: %s at line %d",                     xml_error_string(xml_get_error_code($xml_parser)),                     xml_get_current_line_number($xml_parser)));     } } xml_parser_free($xml_parser); ?>

XML 标记符映射范例

例子 2. 将 XML 映射为 HTML 以下范例将 XML 文档中的标记符直接映射成 HTML 标记符。在“映射数组”中不存在的元素将被忽略。当然，该范例将只对一个特定的 XML 文档有效。 <?php $file = "data.xml"; $map_array = array(     "BOLD"     => "B",     "EMPHASIS" => "I",     "LITERAL"  => "TT" ); function startElement($parser, $name, $attrs) {     global $map_array;     if (isset($map_array[$name])) {         echo "<$map_array[$name]>";     } } function endElement($parser, $name) {     global $map_array;     if (isset($map_array[$name])) {         echo "</$map_array[$name]>";     } } function characterData($parser, $data) {     echo $data; } $xml_parser = xml_parser_create(); // 使用大小写折叠来保证我们能在元素数组中找到这些元素名称 xml_parser_set_option($xml_parser, XML_OPTION_CASE_FOLDING, true); xml_set_element_handler($xml_parser, "startElement", "endElement"); xml_set_character_data_handler($xml_parser, "characterData"); if (!($fp = fopen($file, "r"))) {     die("could not open XML input"); } while ($data = fread($fp, 4096)) {     if (!xml_parse($xml_parser, $data, feof($fp))) {         die(sprintf("XML error: %s at line %d",                     xml_error_string(xml_get_error_code($xml_parser)),                     xml_get_current_line_number($xml_parser)));     } } xml_parser_free($xml_parser); ?>

XML 外部实体范例

该范例能够高亮显示 XML 源代码。它将说明如何外部实体指向处理器来包含和解析其它文档，如何处理 PIs，以及一种确定包含有 PIs 的代码的可信度。

能被该范例使用的的 XML 文档（xmltest.xml 和 xmltest2.xml）被列在该范例之后。

例子 3. 外部实体范例 <?php $file = "xmltest.xml"; function trustedFile($file) {     // only trust local files owned by ourselves     if (!eregi("^([a-z]+)://", $file)         && fileowner($file) == getmyuid()) {             return true;     }     return false; } function startElement($parser, $name, $attribs) {     echo "&lt;<font color=\"#0000cc\">$name</font>";             if (count($attribs)) {                 foreach ($attribs as $k => $v) {             echo " <font color=\"#009900\">$k</font>=\"<font                    color=\"#990000\">$v</font>\"";         }     }     echo "&gt;"; } function endElement($parser, $name) {     echo "&lt;/<font color=\"#0000cc\">$name</font>&gt;"; } function characterData($parser, $data) {     echo "<b>$data</b>"; } function PIHandler($parser, $target, $data) {     switch (strtolower($target)) {         case "php":             global $parser_file;             // If the parsed document is "trusted", we say it is safe             // to execute PHP code inside it.  If not, display the code             // instead.             if (trustedFile($parser_file[$parser])) {                 eval($data);             } else {                 printf("Untrusted PHP code: <i>%s</i>",                         htmlspecialchars($data));             }             break;     } } function defaultHandler($parser, $data) {     if (substr($data, 0, 1) == "&" && substr($data, -1, 1) == ";") {         printf('<font color="#aa00aa">%s</font>',                 htmlspecialchars($data));     } else {         printf('<font size="-1">%s</font>',                 htmlspecialchars($data));     } } function externalEntityRefHandler($parser, $openEntityNames, $base, $systemId,                                   $publicId) {     if ($systemId) {         if (!list($parser, $fp) = new_xml_parser($systemId)) {             printf("Could not open entity %s at %s\n", $openEntityNames,                    $systemId);             return false;         }         while ($data = fread($fp, 4096)) {             if (!xml_parse($parser, $data, feof($fp))) {                 printf("XML error: %s at line %d while parsing entity %s\n",                        xml_error_string(xml_get_error_code($parser)),                        xml_get_current_line_number($parser), $openEntityNames);                 xml_parser_free($parser);                 return false;             }         }         xml_parser_free($parser);         return true;     }     return false; } function new_xml_parser($file) {     global $parser_file;     $xml_parser = xml_parser_create();     xml_parser_set_option($xml_parser, XML_OPTION_CASE_FOLDING, 1);     xml_set_element_handler($xml_parser, "startElement", "endElement");     xml_set_character_data_handler($xml_parser, "characterData");     xml_set_processing_instruction_handler($xml_parser, "PIHandler");     xml_set_default_handler($xml_parser, "defaultHandler");     xml_set_external_entity_ref_handler($xml_parser, "externalEntityRefHandler");     if (!($fp = @fopen($file, "r"))) {         return false;     }     if (!is_array($parser_file)) {         settype($parser_file, "array");     }     $parser_file[$xml_parser] = $file;     return array($xml_parser, $fp); } if (!(list($xml_parser, $fp) = new_xml_parser($file))) {     die("could not open XML input"); } echo "<pre>"; while ($data = fread($fp, 4096)) {     if (!xml_parse($xml_parser, $data, feof($fp))) {         die(sprintf("XML error: %s at line %d\n",                     xml_error_string(xml_get_error_code($xml_parser)),                     xml_get_current_line_number($xml_parser)));     } } echo "</pre>"; echo "parse complete\n"; xml_parser_free($xml_parser); ?>

例子 4. xmltest.xml <?xml version='1.0'?> <!DOCTYPE chapter SYSTEM "/just/a/test.dtd" [ <!ENTITY plainEntity "FOO entity"> <!ENTITY systemEntity SYSTEM "xmltest2.xml"> ]> <chapter> <TITLE>Title &plainEntity;</TITLE> <para> <informaltable> <tgroup cols="3"> <tbody> <row><entry>a1</entry><entry morerows="1">b1</entry><entry>c1</entry></row> <row><entry>a2</entry><entry>c2</entry></row> <row><entry>a3</entry><entry>b3</entry><entry>c3</entry></row> </tbody> </tgroup> </informaltable> </para> &systemEntity; <section id="about"> <title>About this Document</title> <para> <!-- this is a comment --> <?php echo 'Hi! This is PHP version ' . phpversion(); ?> </para> </section> </chapter>

以下文档将被 xmltest.xml 文件调用：

例子 5. xmltest2.xml <?xml version="1.0"?> <!DOCTYPE foo [ <!ENTITY testEnt "test entity"> ]> <foo> <element attrib="value"/> &testEnt; <?php echo "This is some more PHP code being executed."; ?> </foo>