您可以使用先行断言来解决此问题。基本上，我们要说的是我想要一系列特定的字母（例如，ex，ext，x，extension），然后是一个或多个数字。但我们也想涵盖根本没有扩展的情况。
旁注，您不需要在诸如[ s]或其后的[x]之类的单个字符周围加括号。另外，您可以将原本位于同一位置的字符分组，因此可以使用[ s ./]代替
s？。？/?。意思是“这些字符中的任何一个”
这是regex的更新，也可以在这里解决您的评论。我已经在实际代码中添加了解释。
<?php $sPattern = "/^ (?:# Area Code (?:( # Open Parentheses (?=d{3})) # Lookahead. only if we have 3 digits and a closing parentheses )? (d{3}) # 3 Digit area pre (?: (?<=(d{3}) # Closing Parentheses. Lookbehind. ) # only if we have an open parentheses and 3 digits )? [s./-]? # Optional Space Delimeter )? (d{3}) # 3 Digits [s./-]? # Optional Space Delimeter (d{4})s? # 4 Digits and an Optional following Space (?:# Extension (?: # Lets look for some variation of 'extension' (?: (?:e|x|ex|ext).? # First, abbreviations, with an optional following period | extension # Now just the whole word ) s? # Optionsal Following Space ) (?=d+) # This is the Lookahead. only accept that previous section IF it's followed by some digits. (d+) # Now grab the actual digits (the lookahead doesn't grab them) )? # The Extension is Optional $/x"; // /x modifier allows the expanded and commented regex $aNumbers = array( '123-456-7890x123', '123.456.7890x123', '123 456 7890 x123', '(123) 456-7890 x123', '123.456.7890x.123', '123.456.7890 ext. 123', '123.456.7890 extension 123456', '123 456 7890', '123-456-7890ex123', '123.456.7890 ex123', '123 456 7890 ext123', '456-7890', '456 7890', '456 7890 x123', '1234567890', '() 456 7890' ); foreach($aNumbers as $sNumber) { if (preg_match($sPattern, $sNumber, $aMatches)) { echo 'Matched ' . $sNumber . "n"; print_r($aMatches); } else { echo 'Failed ' . $sNumber . "n"; } }?>和输出：
Matched 123-456-7890x123Array( [0] => 123-456-7890x123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 123.456.7890x123Array( [0] => 123.456.7890x123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 123 456 7890 x123Array( [0] => 123 456 7890 x123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched (123) 456-7890 x123Array( [0] => (123) 456-7890 x123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 123.456.7890x.123Array( [0] => 123.456.7890x.123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 123.456.7890 ext. 123Array( [0] => 123.456.7890 ext. 123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 123.456.7890 extension 123456Array( [0] => 123.456.7890 extension 123456 [1] => 123 [2] => 456 [3] => 7890 [4] => 123456)Matched 123 456 7890Array( [0] => 123 456 7890 [1] => 123 [2] => 456 [3] => 7890)Matched 123-456-7890ex123Array( [0] => 123-456-7890ex123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 123.456.7890 ex123Array( [0] => 123.456.7890 ex123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 123 456 7890 ext123Array( [0] => 123 456 7890 ext123 [1] => 123 [2] => 456 [3] => 7890 [4] => 123)Matched 456-7890Array( [0] => 456-7890 [1] => [2] => 456 [3] => 7890)Matched 456 7890Array( [0] => 456 7890 [1] => [2] => 456 [3] => 7890)Matched 456 7890 x123Array( [0] => 456 7890 x123 [1] => [2] => 456 [3] => 7890 [4] => 123)Matched 1234567890Array( [0] => 1234567890 [1] => 123 [2] => 456 [3] => 7890)Failed () 456 7890
