正则表达式匹配模式域\用户名

Question

I'm trying to write a regex for the below pattern, but I'm doing in an incorrect way. Can you please help me? Basically the pattern is like domain\username. Domain should accept alphanumeric plus - as special character, username should only have alphanumeric characters. There should be \ after domain pattern. The regex should be in JavaScript, using String.match() method.

Example:

Desktop-123\john123
Desktop123\john1
Desktop123\john
Desktop-123\john

Regex:

/^[a-zA-Z0-9-]+\[a-zA-Z0-9]$/

Answer 1

If the domain name can not consist of only - , you can first match 1+ alpha numberic chars and optionally repeat a - followed by 1+ alpha numeric chars.

Note to repeat the character class 1 or more times or else you would match a single char.

^[a-zA-Z0-9]+(?:-[a-zA-Z0-9]+)*\\[a-zA-Z0-9]+$

• ^ Start of string
• [a-zA-Z0-9]+ Match 1+ times any of the listed in the character class
• (?:-[a-zA-Z0-9]+)* Optionally repeat a - and any of the listed in the character class
• \\[a-zA-Z0-9]+ Match a \ and again match 1+ times any of the listed in the character class
• $ End of string

Regex demo