php 示例
最后更新于：2022-04-02 04:20:01
[TOC]
## 示例
装饰在 PHP 代码中可谓是标准配置，尤其是在与流式加载相关的代码中
### 概念示例
输出 ``` RESULT: ConcreteComponent RESULT: ConcreteDecoratorB(ConcreteDecoratorA(ConcreteComponent)) ``` ### 文本过滤
([\s\S]*)?|i", // ...
];
private $dangerousAttributes = [
"onclick", "onkeypress", // ...
];
public function formatText(string $text): string
{
$text = parent::formatText($text);
foreach ($this->dangerousTagPatterns as $pattern) {
$text = preg_replace($pattern, '', $text);
}
foreach ($this->dangerousAttributes as $attribute) {
$text = preg_replace_callback('|<(.*?)>|', function ($matches) use ($attribute) {
$result = preg_replace("|$attribute=|i", '', $matches[1]);
return "<" . $result . ">";
}, $text);
}
return $text;
}
}
class MarkdownFormat extends TextFormat
{
public function formatText(string $text): string
{
$text = parent::formatText($text);
// Format block elements.
$chunks = preg_split('|\n\n|', $text);
foreach ($chunks as &$chunk) {
// Format headers.
if (preg_match('|^#+|', $chunk)) {
$chunk = preg_replace_callback('|^(#+)(.*?)$|', function ($matches) {
$h = strlen($matches[1]);
return "" . trim($matches[2]) . " ";
}, $chunk);
} // Format paragraphs.
else {
$chunk = "homepage.
HERE;
// 不过滤
$naiveInput = new TextInput();
echo "======TextInput======".PHP_EOL;
displayCommentAsAWebsite($naiveInput, $dangerousComment);
echo "\n\n\n";
// 过滤标签
$filteredInput = new PlainTextFilter($naiveInput);
echo "======PlainTextFilter======".PHP_EOL;
displayCommentAsAWebsite($filteredInput, $dangerousComment);
echo "\n\n\n";
$dangerousForumPost = <<
performXSSAttack();
HERE;
$naiveInput = new TextInput();
echo "======TextInput======".PHP_EOL;
displayCommentAsAWebsite($naiveInput, $dangerousForumPost);
echo "\n\n\n";
// 过滤标签,过滤Markdown,过滤危险标签
$text = new TextInput();
$markdown = new MarkdownFormat($text);
$filteredInput = new DangerousHTMLTagsFilter($markdown);
echo "======DangerousHTMLTagsFilter======".PHP_EOL;
displayCommentAsAWebsite($filteredInput, $dangerousForumPost);
echo "\n\n\n";
```
输出 ``` ======TextInput====== Hello! Nice blog post! Please visit my homepage. ======PlainTextFilter====== Hello! Nice blog post! Please visit my homepage. performXSSAttack(); ======TextInput====== # Welcome This is my first post on this **gorgeous** forum. ======DangerousHTMLTagsFilter======
';
main.php
``` component = $component; } public function operation(): string{ return $this->component->operation(); } } // 具体装饰类 class ConcreteDecoratorA extends Decorator{ public function operation(): string{ return "ConcreteDecoratorA(".parent::operation().")"; } } //具体装饰类 class ConcreteDecoratorB extends Decorator{ public function operation(): string{ return "ConcreteDecoratorB(".parent::operation().")"; } } function clientCode(Component $component){ // ... echo "RESULT: ".$component->operation(); // ... } $simple = new ConcreteComponent(); clientCode($simple); echo "\n\n"; $decorator1 = new ConcreteDecoratorA($simple); $decorator2 = new ConcreteDecoratorB($decorator1); clientCode($decorator2); ```输出 ``` RESULT: ConcreteComponent RESULT: ConcreteDecoratorB(ConcreteDecoratorA(ConcreteComponent)) ``` ### 文本过滤
main.php
``` inputFormat = $inputFormat; } public function formatText(string $text): string { return $this->inputFormat->formatText($text); } } class PlainTextFilter extends TextFormat { public function formatText(string $text): string { $text = parent::formatText($text); return strip_tags($text); } } class DangerousHTMLTagsFilter extends TextFormat { private $dangerousTagPatterns = [ "|$chunk
"; } } $text = implode("\n\n", $chunks); // Format inline elements. $text = preg_replace("|__(.*?)__|", '$1', $text); $text = preg_replace("|\*\*(.*?)\*\*|", '$1', $text); $text = preg_replace("|_(.*?)_|", '$1', $text); $text = preg_replace("|\*(.*?)\*|", '$1', $text); return $text; } } function displayCommentAsAWebsite(InputFormat $format, string $text) { // .. echo $format->formatText($text); // .. } $dangerousComment = <<输出 ``` ======TextInput====== Hello! Nice blog post! Please visit my homepage. ======PlainTextFilter====== Hello! Nice blog post! Please visit my homepage. performXSSAttack(); ======TextInput====== # Welcome This is my first post on this **gorgeous** forum. ======DangerousHTMLTagsFilter======
Welcome
This is my first post on this gorgeous forum.
```