I'm a beginner in using Regex and have been struggling to create a pattern that can search for a single match of either ! or * anywhere in my string. The full requirements I am looking for are:
- Start with a letter
- Contain at least 1 number
- Between 8-16 characters
- Contain at least one ! or *
What I have so far is:
^[A-Za-z](!*)[A-Za-z0-9]{6,14}$
Clearly I'm using parenthesis incorrectly, but I'm still playing around with it and trying different things. What I am specifically struggling with is searching for a single instance of ! or * in any location.
If anyone can kindly provide a hint, it would be appreciated.
CodePudding user response：
You may use this regex:
^[A-Za-z](?=.*[!*])(?=.*\d).{7,15}$
Explanation:
^: Start[A-Za-z]: Match a letter(?=.*[!*]): Lookahead to assert that we have at least one*or!(?=.*\d): Lookahead to assert that we have at least one digit.{7,15}$: Match 7 to 15 characters (we matched a letter at start)
CodePudding user response：
You can use this pattern:
^[A-Za-z](?=.*\d)(?=.*[!*])[A-Za-z\d!*]{7,15}$
Here (?=.*) means that the order of things you want to exist doesn't matter but they have to be in the string at least one time.