Zend Framework学习之Zend_Filter_StripTags

Strip Tags HTML字符过滤器与Zend_Filter_HtmlEntities过滤器不同，
后者只是将“<”、“>”符号进行转换。而Zend_Filter_StripTags过滤器则是直接过滤掉“<>”符号所包含的内容。 

案例：

<?php

require_once 'Zend/Filter/StripTags.php';

$filter = new Zend_Filter_StripTags();

$temp1 = "<img src = './1.png' width='100px'>";

$temp2 = "<button>aaa</button>";

$temp3 = "<h1>Welcome to Bei Jing</h1>";



echo "内容:".$temp1."<p>经过过滤为：";

echo $filter->filter($temp1);

echo "<p>";



echo "内容:".$temp2."<p>经过过滤为：";

echo $filter->filter($temp2);

echo "<p>";



echo "内容:".$temp3."<p>经过过滤为：";

echo $filter->filter($temp3);

echo "<p>";

结果：

Zend源码分析：

public function filter($value)

    {

        $value = (string) $value;



        // Strip HTML comments first

        while (strpos($value, '<!--') !== false) {

            $pos   = strrpos($value, '<!--');

            $start = substr($value, 0, $pos);

            $value = substr($value, $pos);



            // If there is no comment closing tag, strip whole text

            if (!preg_match('/--\s*>/s', $value)) {

                $value = '';

            } else {

                $value = preg_replace('/<(?:!(?:--[\s\S]*?--\s*)?(>))/s', '',  $value);

            }



            $value = $start . $value;

        }



        // Initialize accumulator for filtered data

        $dataFiltered = '';

        // Parse the input data iteratively as regular pre-tag text followed by a

        // tag; either may be empty strings

        preg_match_all('/([^<]*)(<?[^>]*>?)/', (string) $value, $matches);



        // Iterate over each set of matches

        foreach ($matches[1] as $index => $preTag) {

            // If the pre-tag text is non-empty, strip any ">" characters from it

            if (strlen($preTag)) {

                $preTag = str_replace('>', '', $preTag);

            }

            // If a tag exists in this match, then filter the tag

            $tag = $matches[2][$index];

            if (strlen($tag)) {

                $tagFiltered = $this->_filterTag($tag);

            } else {

                $tagFiltered = '';

            }

            // Add the filtered pre-tag text and filtered tag to the data buffer

            $dataFiltered .= $preTag . $tagFiltered;

        }



        // Return the filtered data

        return $dataFiltered;

    }

我表示看不打懂。。。哈哈哈~