Question

如何从字符串中获取3个单独的正则表达式。我只需要数字，我知道如果我使用\d它会得到所有数字'3/1/1'但我需要3种不同的正则表达式场景？

示例：

  slot/daughter_slot/port  
  3/1/1     regexp for slot only?
  3/1/10    regexp for daughter_slot only?
  3/1/2     regexp for port only?

感谢，

Answer 1

仅适用于插槽的正则表达式

^/d+

示例http://regex101.com/r/eV2hI2/1

仅针对daughter_slot的regexp？

\/(\d+)\/

匹配组1包含数字

示例http://regex101.com/r/eV2hI2/4

仅适用于端口的regexp？

\d+$

示例http://regex101.com/r/eV2hI2/2

Answer 2

仅适用于插槽的正则表达式

\d+/.+/.+

仅适用于daughter_slot的正则表达式

.+/\d+/.+

regexp仅限端口

.+/.+/\d+

Answer 3

如果您不假设字符串以数字开头并以数字结尾，并且只包含数字或斜杠，并且您只想匹配相应的数字。

注意：JavaScript不支持lookbehind（？＆lt; ...），因此这可能不适用于您的环境。此外，可能必须转义正斜杠（/）（\ /）。

仅限广告位example）

(?<!/|\d)\d+(?=/)

仅限子槽（example）

(?<=/(?=\d+/))\d+

仅端口（example）

(?<=/)\d+(?!/|\d)

仅适用于插槽的说明

(?<!/|\d) - Assert that the previous character is neither / nor a digit
\d+       - Match a sequence of digits
(?=/)     - Assert that the next character is a /

仅限子槽说明

\d+       - Match a sequence of digits
(?<=/())  - Assert that this sequence is preceded by a /...
   ?=\d+/ - ... which is followed by a sequence of digits followed by a /

仅限端口

的说明

(?<=/)    - Assert that the previous character is a /
\d+       - Match a sequence of digits
(?!/|\d)  - Assert that the following character is neither a digit nor a /

Answer 4

试试这个：

    $re = "/(?<slot>\\d+)\\/(?<daughter_slot>\\d+)\\/(?<port>\\d+)/m";
    $str = " slot/daughter_slot/port \n 3/1/1 regexp for slot only?\n 3/1/10 regexp for daughter_slot only?\n 3/1/2 regexp for port only?";

    preg_match_all($re, $str, $matches);
    var_dump($matches);

see live demo

使用正则表达式使用反斜杠解析数字字符串

4 个答案: