php - 正则表达式基础 : grab text between two constants

Question

卡在 PHP 中的一个(相当简单的)正则表达式问题上。

这一部分隐藏在一堆文字中:

  <tr>
        <td id="descriptionArea">
            Customer request to remove "Intro - 01/13/09" video clip.
            <br/>
        </td>
    </tr>

我想要介于两者之间的任何东西:

descriptionArea">

...和...

</td>

friend 建议:

$pattern = '<td="descriptionArea">\s*(.*?)\s*<';
$clean = preg_replace("'[\n\r\s\t]'","",$text); // to rid of line breaks
preg_match($pattern, $clean, $matches);
print_r($matches);

但是我得到以下错误:

Warning: preg_match() [function.preg-match]: Unknown modifier 'q'

我想第二个问题是 preg_match 是否也是正确的 PHP 函数。我应该改用 ereg 吗？感谢您的帮助。

Answer 1

使用 preg_* 时函数，第一个字符或模式被视为分隔符:

The expression must be enclosed in the delimiters, a forward slash (/), for example. Any character can be used for delimiter as long as it's not alphanumeric or backslash (\). If the delimiter character has to be used in the expression itself, it needs to be escaped by backslash. Since PHP 4.0.4, you can also use Perl-style (), {}, [], and <> matching delimiters.
— Regular Expressions (Perl-Compatible) – Introduction

所以你不需要转义或替换&正如其他人所说的那样。而是使用适当的定界符并在表达式中转义这些字符:

'/<td id="descriptionArea">(.*?)<\/td>/'