博客文章段落如何截取？

Question

你想要的结果是什么样子的呢？参考手册这一章或许对你有帮助：
http://cn2.php.net/manual/zh/faq.html.php

Answer 1

$str = '原始数据';
[code=PHP]
//得到除了链接外的转化文本
$str = preg_replace(
    array("'([\r\n])[\s]+'",
          "'&(quot|#34);'i",
          "'&(amp|#38);'i",
          "'&(lt|#60);'i",
          "'&(gt|#62);'i",
          "'&(nbsp|#160);'i",
          "'&(iexcl|#161);'i",
          "'&(cent|#162);'i",
          "'&(pound|#163);'i",
          "'&(copy|#169);'i",
          "'&#(\d+);'e"),
    array("\\1",
          "\"",
          "&",
          "<",
          ">",
          " ",
          chr(161),
          chr(162),
          chr(163),
          chr(169),
          "chr(\\1)"),
    strip_tags($str, '<a>'));
//2、用mb_substr或类似的函数截取即可
[/php]

Answer 2

//得到除了链接外的转化文本
$str   =   preg_replace(
        array("'([\r\n])[\s]+'",
                    "'&(quot ¦#34);'i",
                    "'&(amp ¦#38);'i",
                    "'&(lt ¦#60);'i",
                    "'&(gt ¦#62);'i",
                    "'&(nbsp ¦#160);'i",
                    "'&(iexcl ¦#161);'i",
                    "'&(cent ¦#162);'i",
                    "'&(pound ¦#163);'i",
                    "'&(copy ¦#169);'i",
                    "'&#(\d+);'e"),
        array("\\1",
                    "\"",
                    "&",
                    " <",
                    "> ",
                    "   ",
                    chr(161),
                    chr(162),
                    chr(163),
                    chr(169),
                    "chr(\\1)"),
        strip_tags($str,   ' <a> '));
//2、用mb_substr或类似的函数截取即可

Answer 3

..... 不好意思，那个正则没看懂，麻烦帮我看下怎么改下面的代码吧？$str = '<img src="a.gif" /><a href="a.html">a</a>asdfsdfsdf';
echo  mb_strcut($str, 0, 20, 'utf-8'); 怎么给回复的人加分？？