CODEWITHSUNDEEP
regexgrailsgroovy
chemilleX3
chemilleX3

Reputation: 1196

How to write a matches for input that contains alphanumeric and special characters

I have a problem with my matches. I have a field that that SHOULD accept a value that may contain any combination of alphanumeric and special characters. I have a code that works fine when the input is a 1) combination of alphanumeric and special characters, and 2) alphanumeric. But if the input contains a combination of either 1) number and special characters ONLY without alphabet or 2) alphabet and special characters ONLY without number, I got an error on my matches. What I wanted to do is to create a matches that best works on the following input combinations:

1) alphabet+number
2) alphabet+special character
3) alphabet+number+special character
4) number+special character

This is my code:

matches: /^(?=.*[0-9]+.*)(?=.*[a-zA-Z]+.*)[0-9a-zA-Z_\[\]\\\^\$\.\|\?\*\+\(\)~!@#%&-=]{8,}$/

I need your suggestions! Thanks!

Upvotes: 0

Views: 797

Answers (2)

kasavbere
kasavbere

Reputation: 6003

 /^(?=.*[a-zA-Z0-9]+.*)[_\[\]\\\^\$\.\|\?\*\+\(\)~!@#%&-=]{8,}$/

Upvotes: 0

mathematical.coffee
mathematical.coffee

Reputation: 56915

It's because your positive lookahead requires both a [0-9] to be present and a [a-zA-Z] to be present.

Try reducing this to one single lookahead, which just specifies that at least one of [0-9] and [a-zA-Z] be present:

matches: /^(?=.*[0-9a-zA-Z])[0-9a-zA-Z_\[\]\\\^\$\.\|\?\*\+\(\)~!@#%&-=]{8,}$/

Furthermore, you can improve on the efficiency of the regex by modifying the .* in your lookahead to be [^0-9a-zA-Z]*: that way the lookahead matches the first alphanumeric it finds and then stops, preventing needless scanning:

matches: /^(?=[^0-9a-zA-Z]*[0-9a-zA-Z])[0-9a-zA-Z_\[\]\\\^\$\.\|\?\*\+\(\)~!@#%&-=]{8,}$/

Upvotes: 1

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