匹配带有特殊字符的正则表达式

Question

have a test string .

1. consists of 8 digits.
2. must have --- , - , . or : separator such that string gets divided in parts, with each part having exactly two digits.
3. string must have exactly one kind of separator.
4. Separators must have integers on both sides

i am not able to met 3rd condition

My answer : ^(\\d{2}(([-]{3})|.|:|-)){3}(\\d){2}$

Example: 1. 11---11---11---11 2. 11:11:11:11

Please help .

Answer 1

Note that the requirements translate to the string having the form ##:##:##:## , ie two numbers, following by separator, etc.

You can use patterns for each separator type along with an alternation to include all four separator types:

^(?:\d{2}---\d{2}---\d{2}---\d{2})|
 (?:\d{2}-\d{2}-\d{2}-\d{2})|
 (?:\d{2}\.\d{2}\.\d{2}\.\d{2})|
 (?:\d{2}:\d{2}:\d{2}:\d{2})$

I broke the regex up into multiple lines for readability.

Demo here:

Regex101

This regex could be simplified to this:

^(?:\d{2}---){3}\d{2}|(?:\d{2}-){3}\d{2}|(?:\d{2}:){3}\d{2}|(?:\d{2}\.){3}\d{2}$

But I actually prefer the longer open form because it is easier to read.

Answer 2

更简单的答案：^（？：\\ d {2}（-）{3}）{3} \\ d {2} |（？：\\ d {2}-）{3} \\ d {2} |（？ ：\\ d {2}：）{3} \\ d {2} |（?? \\ d {2}。）{3} \\ d {2} $