What is the correct pattern for a text input to only allow uppercase letters, lowercase letters, and commas?
I know that this is correct for the letters:
pattern="[a-zA-Z]"
but I dont know how to allow commas.
Thanks for any help!
Short answer:
pattern="^[a-zA-Z,]*$"
A couple of comment:
* means zero or more characters which means this patter will allow empty fields as well. If you want to guarantee that it will contain at least one character, use + instead of *.
^ means beginning of the string and $ is the end. If you don't use them then something like this would be possible "!#123asdSDADS,,,21312312(2"
Related
I want to create a pattern for an HTML input field that needs to have at least 10 numbers in it and may also have spaces and a plus sign on top of that, but it's not required.
It's important that numbers and spaces can be mixed though. Also, the whole field can only have 17 characters all in all.
I'm not sure if it's even possible. I started doing something like that:
pattern="[0-9+\s]{10,17}*"
But like this, it's not guaranteed that there are at least 10 numbers.
Thanks in advance! Hope the question doesn't exist already, I looked but couldn't find it.
You can use
pattern="(?:[+\s]*\d){10,17}[+\s]*"
The regex matches
(?:[+\s]*\d){10,17} - ten to seveteen occurrences of zero or more + or whitespaces and then a digit
[+\s]* - zero or more + or whitespaces.
Note the pattern is anchored by default (it is wrapped with ^(?: and )$), so nothing else is allowed.
Is it possible to limit a simple form input to only 50 characters without javascript?
I have used the max_length attribute, however this includes blank spaces which is not what i want.
I've attempted to use pattern (as suggested on another post), but i can't seem to get that to work either.
Thanks
I don't know why you don't want it to include blanks.
Usually I use max_length including blanks and leave it to the user to trim their excess whitespace. I'm not disagreeing, I honestly don't know what your requirement is.
If you want to allow leading and trailing whitespace, but are willing to leave it to the user to replace excess whitespace within the text to one whitespace character then this is the pattern you want:
<input pattern="^\s*.{0,50}\s*$">
Sometimes for multiline regular expressions, \A is used instead of ^ and \z is used instead of $, but I'm not sure HTML supports that in their regular expressions.
My form field is for users to enter their first name, I want users to be allowed to put a space "billy bob", but MUST require a letter.
My code:
pattern="[a-zA-Z\s]+"
This accepts, letters and spaces. How can I modify it to require the use of at least 1 letter. I want to avoid users entering a name that is all spaces.
Thanks!
Something like this should do it:
([a-zA-Z]+\s*)+
We're saying that we need at least 1 letter [a-zA-Z]+ followed by zero or many spaces \s* and we repeat the whole thing one or many times ([a-zA-Z]+\s*)+
The above will work if you don't want the name to start with spaces otherwise you can use:
(\s*[a-zA-Z]+\s*)+
That's the same pattern but with zero or many leading spaces \s*
I think this works for you.
It is only accept letter and spaces.
^[a-zA-Z\s]*$
I have a regex '^[A0-Z9]+$' that works until it reaches strings with 'special' characters like a period or dash.
List:
UPPER
lower
UPPER lower
lower UPPER
TEST
test
UPPER2.2-1
UPPER2
Gives:
UPPER
TEST
UPPER2
How do I get the regex to ignore non-alphanumeric characters also so it includes UPPER2.2-1 also?
I have a link here to show it 'real-time': http://www.rubular.com/r/ev23M7G1O3
This is for MySQL REGEX
EDIT: I didn't specify I wanted all non-alphanumeric characters (including spaces), but with the help of others here it led me to this: '^[A-Z-0-9[:punct:][:space:]]+$' is there anything wrong with this?
Try
'^[A-Z0-9.-]+$'
You just need to add the special characters to the group, optionally escaping them.
Additionally if you choose not to escape the -, be aware that it should be placed at the start or the end of the grouping expression to avoid the chance that it may be interpreted as delimiting a range.
To your updated question, if you want all non-whitespace, try using a group such as:
^[^ ]+$
which will match everything except for a space.
If instead what you wanted is all non-whitespace and non-lowercase, you likely will want to use:
^[^ a-z]+$
The 'trick' used here is adding a caret symbol after the opening [ in the group expression. This indicates that we want the negation of the match.
Following the pattern, we can also apply this 'trick' to get everything but lowercase letters like this:
^[^a-z]+$
I'm not really sure which of the 3 above you want, but if nothing else, this ought to serve as a good example of what you can do with character classes.
I believe you are looking for (one?) uppercase-word match, where word is pretty much anything.
^[^a-z\s]+$
...or if you want to allow more words with spaces, then probably just
^[^a-z]+$
You just need to put in the . and -. In theory, you don't need to escape because they are inside the brackets, but I like to to remind myself to escape when I have to.
'^[A-Z0-9\.\-]+$'
Try regular expression as below:
'^[A0-Z0\\.\\-]+$'
I am writing a custom search engine for my website. I am trying to make use of MySQL REGEXP feature. I would like to be able to search for a word separated by spaces to avoid the chances of getting suffixes or prefixes on a word. For example I am trying to search for "appreciate" I want appreciate, not appreciated or unappreciate or unappreciated. Any ideas on how I could do this with MySQL's REGEXP? My idea for this was to look for spaces like maybe so:
^appreciate$|^appreciate[:space:]|[:space:]appreciate$|[:space:]appreciate[:space:]
I am sure they is a better way of doing it and I have no idea if that even works
I think what you want is something like this:
SELECT 'I appreciate you' REGEXP '[[:<:]]appreciate[[:>:]]'; /* matches */
[[<:]] and [[>:]] are word boundaries. From the manual:
These markers stand for word boundaries. They match the beginning and end of words, respectively. A word is a sequence of word characters that is not preceded by or followed by word characters. A word character is an alphanumeric character in the alnum class or an underscore (_).
Edit: just to clarify, this also deals with situations where there's a newline character after the word, or a comma, etc
What about:
^\s*appreciate(\s+.*)*$
Between the start and the word there may be 0+ whitespace parts
then comes the word
then if something comes after that, it has to start with whitespace
You can seek for non-alphabetic characters:
[^[:alpha:]]+
... or just word boundaries:
[[:<:]]foo[[:>:]]
Before making a choice, don't forget to make some tests with commas, dots and non-English chars. Also, take into account that MySQL does not fully support regular expressions in multi-byte strings (such as UTF-8).