正则表达式：用特殊字符匹配单词

Question

我正在尝试找到一个正则表达式，该正则表达式与字符串中的一个单词（确切的单词）匹配。 问题是该单词具有特殊字符（如“＃”或其他任何字符）时。 特殊字符可以是任何UTF-8字符，例如（“áéíóúñ＃@”），并且必须忽略标点符号。

我举了一些我要找的例子：

Searching:#myword

 Sentence: "I like the elephants when they say #myword" <- MATCH
 Sentence: "I like the elephants when they say #mywords" <- NO MATCH
 Sentence: "I like the elephants when they say myword" <-NO MATCH
 Sentence: "I don't like #mywords. its silly" <- NO MATCH
 Sentence: "I like #myword!! It's awesome" <- MATCH
 Sentence: "I like #myword It's awesome" <- MATCH

PHP示例代码：

 $regexp= "#myword";
    if (preg_match("/(\w$regexp)/", "I like #myword!! It's awesome")) {
        echo "YES YES YES";
    } else {
        echo "NO NO NO ";
    }

谢谢！

更新：如果我查找“ myword ”，则该单词必须以“ w”开头，而不是另一个字符。

Sentence: "I like myword!! It's awesome" <- MATCH
Sentence: "I like #myword It's awesome" <-NO MATCH

Answer 1

当分别考虑字符和边界时，将产生以下解决方案。 也可能存在一种直接使用单词边界的可行方法。

码：

function search($strings,$search) {
        $regexp = "/(?:[[:space:]]|^)".$search."(?:[^\w]|$)/i";
        foreach ($strings as $string) {
                echo "Sentence: \"$string\" <- " . 
                     (preg_match($regexp,$string) ? "MATCH" : "NO MATCH") ."\n";
        }
}

$strings = array(
"I like the elephants when they say #myword",
"I like the elephants when they say #mywords",
"I like the elephants when they say myword",
"I don't like #mywords. its silly",
"I like #myword!! It's awesome",
"I like #mywOrd It's awesome",
);
echo "Example 1:\n";
search($strings,"#myword");

$strings = array(
"I like myword!! It's awesome",
"I like #myword It's awesome",
);
echo "Example 2:\n";
search($strings,"myword");

输出：

Example 1:
Sentence: "I like the elephants when they say #myword" <- MATCH
Sentence: "I like the elephants when they say #mywords" <- NO MATCH
Sentence: "I like the elephants when they say myword" <- NO MATCH
Sentence: "I don't like #mywords. its silly" <- NO MATCH
Sentence: "I like #myword!! It's awesome" <- MATCH
Sentence: "I like #mywOrd It's awesome" <- MATCH
Example 2:
Sentence: "I like myword!! It's awesome" <- MATCH
Sentence: "I like #myword It's awesome" <- NO MATCH

Answer 2

您应该使用// /\\bmyword\\b/这样的myword边界搜索myword 。
#本身也是一个单词边界，因此/\\b#myword\\b/不起作用。
一个想法是用\\X转义unicode字符，但这会带来其他问题。

/ #myword\b/

Answer 3

这应该可以解决问题（将“ myword”替换为您要查找的任何内容）：

^.*#myword[^\w].*$

如果匹配成功，那么您找到了答案-否则没有找到。