I use the following regex to validate a text box's content:
^[A-Za-z.]*[A-Za-z][-A-Za-z0-9,/()&:. ]*$
I would like to validate the length of my text-box in this regexp.
1 Answer
To check a string's length and format with a regex, you can use numbered repeaters:
^[a-z]{1,128}$
However, if you have a succession of unkown numbers of character classes, you can use zero-length positive lookeahead at the beginning of the regex:
^(?=.{1,128}$)[a-z]*[a-z0-9]*$
So for your regex:
^(?=.{1,128}$)[A-Za-z.]*[A-Za-z][-A-Za-z0-9,/()&:. ]*$
If you can though, I'd still suggest checking myString.length instead.
4 Comments
Tom Lord
That is some of the ugliest, most unnecessary regex I've ever seen... And I'm almost certain it won't do the intended job properly. It could match: ".....a ,", but would fail to match "(test)" or "123".
instanceof me
According to his regex, he doesn't want to match those…
Tom Lord
I know. My point is that the original question was clearly misleading, in that you've been asked to solve the incorrect problem in an incorrect way.
instanceof me
Okay, I assumed that the comment being on my answer, you were criticizing the answer
maxlengthproperty.maxlengthattribute. On textarea, you have to manually check the value length.