由点分隔的两部分字符串的正则表达式

Question

I need to write a regular expression for a string of two parts which is separated by '.' Here below are the condition,

1. <<1st part>>.<<2nd part>> : Example- Time01.Sheet
2. 1st part should contain alpha numeric characters and it must contain at least 1 uppercase alphabet, 1 lowercase alphabet, and 1 number.
3. 2nd part should contain alpha numeric characters.

My code : ((?=.*[az])(?=.*[AZ])(?=.*[0-9])(?=\\\\S+$).*)[.]([\\\\w]+)$

Input : Vijay.hello876IUY

Actual Output : Valid data

Expected Output : Invalid data (Because 1st part doesn't contain any numbers)

Any one please help me to solve this...

Answer 1

You may use

^(?=[^.]*[a-z])(?=[^.]*[A-Z])(?=[^.]*[0-9])[a-zA-Z0-9]+\.[a-zA-Z0-9]+$

See the regex demo .

Details

• ^ - start of string
• (?=[^.]*[az]) - there must be a lowercase ASCII letter after 0+ chars other than .
• (?=[^.]*[AZ]) - there must be an uppercase ASCII letter after 0+ chars other than .
• (?=[^.]*[0-9]) - there must be a digit after 0+ chars other than .
• [a-zA-Z0-9]+ - 1+ alphanumeric chars
• \\. - a dot
• [a-zA-Z0-9]+ - 1+ alphanumeric chars
• $ - end of string.

In Java:

s.matches("(?=[^.]*[a-z])(?=[^.]*[A-Z])(?=[^.]*[0-9])[a-zA-Z0-9]+\\.[a-zA-Z0-9]+")

Since matches() requires a full string match, you need no ^ at the beginning and $ anchor at the end.