php - 如何在 PHP 中验证 XML 的 CDATA 部分

Question

我根据用户输入创建了一个 XML。其中一个 xml 节点有一个 CDATA 部分。如果 CDATA 部分中插入的字符之一是“特殊”(我认为是控制字符)，则整个 xml 将无效。

例子:

$dom = new DOMDocument('1.0', 'utf-8');
$dom->appendChild($dom->createElement('root'))
    ->appendChild($dom->createCDATASection(
        "This is some text with a SOH char \x01."
    ));

$test = new DOMDocument;
$test->loadXml($dom->saveXML());
echo $test->saveXml();

会给予

Warning: DOMDocument::loadXML(): CData section not finished
This is some text with a SOH cha in Entity, line: 2 in /newfile.php on line 17

Warning: DOMDocument::loadXML(): PCDATA invalid Char value 1 in Entity, line: 2 in /newfile.php on line 17

Warning: DOMDocument::loadXML(): Sequence ']]>' not allowed in content in Entity, line: 2 in /newfile.php on line 17

Warning: DOMDocument::loadXML(): Sequence ']]>' not allowed in content in Entity, line: 2 in /newfile.php on line 17

Warning: DOMDocument::loadXML(): internal errorExtra content at the end of the document in Entity, line: 2 in /newfile.php on line 17
<?xml version="1.0"?>

在 php 中是否有确保 CDATA 部分有效的好方法？

Answer 1

允许的range of characters对于 CDATA section是

#x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF]

因此您必须清理您的字符串以仅包含这些字符。