<?php
// $document 应包含一个 HTML 文档。

// 本例将去掉 HTML 标记，javascript 代码

// 和空白字符。还会将一些通用的

// HTML 实体转换成相应的文本。


$search = array ("'<script[^>]*?>.*?</script>'si", // 去掉 javascript
                 "'<[/!]*?[^<>]*?>'si", // 去掉 HTML 标记
                 "'([rn])[s]+'", // 去掉空白字符
                 "'&(quot|#34);'i", // 替换 HTML 实体
                 "'&(amp|#38);'i",
                 "'&(lt|#60);'i",
                 "'&(gt|#62);'i",
                 "'&(nbsp|#160);'i",
                 "'&(iexcl|#161);'i",
                 "'&(cent|#162);'i",
                 "'&(pound|#163);'i",
                 "'&(copy|#169);'i",
                 "'&#(d+);'e"); // 作为 PHP 代码运行

$replace = array ("",
                  "",
                  "1",
                  """,
                  "&",
                  "<",
                  ">",
                  " ",
                   chr(161),
                   chr(162),
                   chr(163),
                   chr(169),
                  "chr(1)");

$text = preg_replace ($search, $replace, $document);
?>