捕获大于小数点后 1 位的数字

或带有isg选项的此模式

site.*?'D'K('d+'.'d{2})  

演示
解释：

site            # "site"
.               # Any character except line break
*?              # (zero or more)(lazy)
'D              # <character that is not a digit>
'K              # <Reset start of match>
(               # Capturing Group (1)
  'd            # <digit 0-9>
  +             # (one or more)(greedy)
  '.            # "."
  'd            # <digit 0-9>
  {2}           # (repeated {2} times)
)               # End of Capturing Group (1)

要匹配 0.00 到 9.99 之间的十进制数，请使用：

'b'd'.'d{2}'b

怎么样？

$re = "~(site.*?'s+)('d+'.'d+)~mis";

只需在正则表达式中添加单词边界'b：

$re = "/(?:site(?:''.com)?[''s''w''d^]*)'b(''d+''.''d{2})/i"; 
//                             here  ___^^
$str = "Debit card payment to site.com
    Germany
    on 01 May 1.30
    Debit card payment to  site Germany
    on 01 May 4.63
     Debit card payment to site.Com
    Germany
    on 01 May 3.30
    Debit card payment to Paypal *Xiao
    Ref:- 23948 0000000000 32.98
    Debit card payment to site.Com
    Germany
    on 20 May 17.49
    Debit card refund from site.Com
    Germany
    on 21 May 429.29 ";
preg_match_all($re, $str, $matches);
print_r($matches)

输出：

Array
(
    [0] => Array
        (
            [0] => site.com
    Germany
    on 01 May 1.30
            [1] => site Germany
    on 01 May 4.63
            [2] => site.Com
    Germany
    on 01 May 3.30
            [3] => site.Com
    Germany
    on 20 May 17.49
            [4] => site.Com
    Germany
    on 21 May 429.29
        )
    [1] => Array
        (
            [0] => 1.30
            [1] => 4.63
            [2] => 3.30
            [3] => 17.49
            [4] => 429.29
        )
)

你只需要改变一个字符：

从

$re = "/(?:site(?:''.com)?[''s''w''d^]*)(''d+''.''d{2})/i";

自

$re = "/(?:site(?:''.com)?[''s''w''d^]*?)(''d+''.''d{2})/i"; 
                                       ^

*?代表非贪婪匹配，即表达式不会尝试尽可能多地匹配，而只是在必要时进行匹配。这样它就不会吃掉所有的数字。