PHP正则表达式需要特殊查律器上的帮助 - php regular expression help needed on special charecters

php regular expression help needed on special charecters

本文关键字：帮助正则表达式 PHP | 更新日期: 2023-09-27

这是我的代码

    $string="According to a report on the Times of In#dia, &#8220 Telan#gana Rashtra Samiti chief K Chandrasekhar #Rao has seen a #sinister motive behind the protests against the formation of Telangana";
preg_match_all('/(?!'b)(#'w+'b)/' ,$string, $matches);
foreach($matches[1] as $match){
$string = str_replace("$match","[h]".$match."[/h]",$string);
}
echo $string;

输出

根据In#dia的报道，&[h]#8220[/h] Telan#gana Rashtra Samiti首席执行官K Chandrasekhar [h]#Rao[/h]已经看到了一个 [h]#sinister[/h] 抗议成立的动机特伦甘纳邦

我只想替换以 # 开头的字符串，但它也替换了&#8220 &[h]#8220[/h]. 请帮我解决这个问题。

尝试使用积极的回溯，因为在哈希#之前总是有一个单词边界：

/(?<='s|^)(#'w+'b)/

这可确保在哈希单词之前有一个空格或字符串的开头。

您可以在preg_replace中使用它：

$string="According to a report on the Times of In#dia, &#8220 Telan#gana Rashtra Samiti chief K Chandrasekhar #Rao has seen a #sinister motive behind the protests against the formation of Telangana";
$result = preg_replace('/(?<='s|^)(#'w+'b)/', "[h]$1[/h]", $string);