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在PHP中使用正则表达式选择性地替换标签外的单词?

preg-replace php

Gary Willoughby · 技术社区 · 14 年前

我有一段文字,我想用php替换一些单词(preg_replace)。以下是一段文本示例:

This lesson addresses rhyming [one]words and ways[/one] that students may learn to identify these words. Topics include learning that rhyming words sound alike and these sounds all come from the [two]ending of the words[/two]. This can be accomplished by having students repeat sets of rhyming words so that they can say them and hear them. The students will also participate in a variety of rhyming word activities. In order to demonstrate mastery the students will listen to [three]sets of words[/three] and tell the teacher if the words rhyme or not.

如果你注意到“单词”这个词有很多出现。我想取代所有那些不要出现在任何带有“birds”字样的标签中。所以看起来是这样的:

This lesson addresses rhyming [one]words and ways[/one] that students may learn to identify these birds. Topics include learning that rhyming birds sound alike and these sounds all come from the [two]ending of the words[/two]. This can be accomplished by having students repeat sets of rhyming birds so that they can say them and hear them. The students will also participate in a variety of rhyming word activities. In order to demonstrate mastery the students will listen to [three]sets of words[/three] and tell the teacher if the birds rhyme or not.

您会使用正则表达式来完成这个任务吗?
罐头正则表达式可以做到这一点?

1 回复 | 直到 13 年前

cletus 14 年前

您所拥有的标记没有定义一种常规语言,因此,正则表达式不能很好地实现这一点。我认为你能做的最好的事情就是移除所有的标签(用其他东西替换它们),用“birds”替换“words”,然后把内容放回原处。

$str = preg_replace_callback('!\[one\].*?\[/one\]!s', 'hash_one', $input);
$str = str_replace('words', 'birds', $str);
$output = preg_replace_callback('!:=%\w+%=:!', 'replace_one', $str);

$hash = array();

function hash_one($matches) {
  global $hash;
  $key = ':=%' . md5($matches[0]) . '%=:'; // to ensure this doesn't occur naturally
  $hash[$key] = $matches[0];
  return $key;
}

function replace_one($amtches) {
  global $hash;
  $ret = $hash[$matches[0]];
  return $ret ? $ret : $matches[0];
}